## MATH - SCIENCE DICTIONARY

salt - ionic compound formed by reacting an acid and a base; sometimes refers only to sodium chloride, NaCl

Zaitsev rule - rule in organic chemistry that states alkene formation from an elimination reaction will produce more highly substituted alkenes

A- Absolute Alcohol to Azimuthal Quantum Number

Abacus: An early counting tool used for basic arithmetic

absolute alcohol - common name for high purity ethanol or ethyl alcohol

absolute error - expression of the uncertainty or inaccuracy of a measurement

absolute temperature - temperature measured using the Kelvin scale

absolute uncertainty - the uncertainty of a scientific measurement, given in the same units as the measurement

Absolute Value: Always a positive number, absolute value refers to the distance of a number from 0.

absolute zero - the lowest possible state at which matter can exist, 0 K or -273.15°C

absorbance - measure of the amount of light absorbed by a sample

absorption - process by which atoms, ions, or molecules enter a bulk phase

absorption spectroscopy - technique used to determine concentration and structure of a sample based on which wavelengths of liquid are absorbed

absorption spectrum - graph of amount of absorption as a function of wavelength

absorptivity - absorption cross section of extinction coefficient, which is the absorbance of a solution per unit path length and concentration

abstract algebra: the area of modern mathematics that considers algebraic structures to be sets with operations defined on them, and extends algebraic concepts usually associated with the real number system to other more general systems, such as groups, rings, fields, modules and vector spaces

accuracy - the closeness of a measurement to a true or accepted value

acid - a chemical species that accepts electrons or donate protons or hydrogen ions

acid anhydride - a nonmetal oxide that reacts with water to form an acidic solution

acid dissociation constant - Ka - a quantitative measure of how strong an acid is

acid-base indicator - a weak acid or weak base that changes color when the concentration of hydrogen or hydroxide ions changes in an aqueous solution

acid-base titration - a procedure to find the concentration of an acid or base by reacting a known concentration with the unknown until the equivalence point is reached

acidic solution - an aqueous solution with a pH less than 7.0

actinides - Usually, the actinides are considered to be elements 90 (thorium) through 103 (lawrencium) Otherwise, the actinides are defined according to their common properties

actinium - the name for the element with atomic number 89 and is represented by the symbol Ac It is a member of the actinide group

activated complex - an intermediate state at the maximum energy point on the reaction path that occurs as reactants are being converted into product in a chemical reaction

activation energy - Ea - the minimum amount of energy needed for a chemical reaction to occur

active transport - the movement of molecules or ions from a region of lower concentration to higher concentration; requires energy

activity series - list of metals ranked in order of decreasing activity, used to predict which metals displace others in aqueous solutions

actual yield - the quantity of product experimentally obtained from a chemical reaction

Acute angle – An angle which measures below 90°.

Acute Angle: An angle whose measure is between 0° and 90° or with less than 90° radians

Acute coronary syndrome: decreased blood flow in the coronary arteries resulting in reduced circulation rate and inadequate oxygenation of the myocardial muscle

acute health effect - the effect caused by initial exposure to a chemical

Acute Kidney Injury (AKI): Abrupt loss of kidney function that develops within 7 days, it is a broad clinical syndrome encompassing various etiologies, including specific kidney diseases, which can occur in the community, as well as in the hospital or ICU

Acute triangle – A triangle containing only acute angles.

acyl group - a functional group with the formula RCO- where R is bound to carbon via a single bond

Addend: A number involved in an addition problem; numbers being added are called addends

Additive inverse – The opposite of a number or its negative A number plus its additive inverse equals 0

Adjacent angles – Angles with a common side and vertex.

adsorption - the adhesion of a chemical species onto a surface

adulterant - a chemical that acts as a contaminant in the context of another substance's purity

aether - a medium believed to carry light waves in the 18th and 19th century

air - the mixture of gases that make up the Earth's atmosphere, consisting mainly of nitrogen, with oxygen, water vapor, argon, and carbon dioxide

alchemy -Several definitions of alchemy exist Originally, alchemy was an ancient tradition of sacred chemistry used to discern the spiritual and temporal nature of reality, its structure, laws, and functions

alcohol - a substance that contains an -OH group attached to a hydrocarbon

algebra: a branch of mathematics that uses symbols or letters to represent variables, values or numbers, which can then be used to express operations and relationships and to solve equations

Algebra: The branch of mathematics that substitutes letters for numbers to solve for unknown values

algebraic equation: a combination of numbers and letters equivalent to a sentence in language, e.g y = x2 + 3x – 4

algebraic expression: a combination of numbers and letters equivalent to a phrase in language, e.g x2 + 3x – 4

Algorithm: A procedure or set of steps used to solve a mathematical computation

algorithm: a step by step procedure by which an operation can be carried out

aliphatic amino acid - amino acid that has an aliphatic side chain

aliphatic compound - an organic compound containing carbon and hydrogen joined into straight chains, branches chains, or non-aromatic rings

aliphatic hydrocarbon - a hydrocarbon containing carbon and hydrogen joined into straight chains, branches chains, or non-aromatic rings

alkali metal - any element found in group IA (first column) of the periodic table

alkaline - an aqueous solution with a pH greater than 7

alkalinity - a quantitative measure of a solution's ability to neutralize an acid

Alkalinity is a measure of how basic a substance is

alkene - a hydrocarbon containing a double carbon-carbon bond

alkenyl group - the hydrocarbon group formed when a hydrogen atom is removed from an alkene group

alkoxide - an organic functional group formed when a hydrogen atom is removed from the hydroxyl group of an alcohol when it is reacted with a metal

alkoxy group - functional group containing an alkyl group bonded to oxygen

allotrope - a form of an elemental substance

alloy - substance made by melting together two or more elements, at least one of which must be a metal

alpha decay - spontaneous radioactive decay which produces an alpha particle or helium nucleus

alpha radiation - the ionizing radiation released from radioactive decay emitting an alpha particle

aluminum or aluminium - the name for the element with atomic number 13 and is represented by the symbol Al It is a member of the metal group

amalgam - any alloy of mercury and one or more other metals

americium - radioactive metal with element symbol Am and atomic number 95

amicable numbers: pairs of numbers for which the sum of the divisors of one number equals the other number, e.g 220 and 284, 1184 and 1210

amide - functional group containing a carbonyl group linked to a nitrogen atom

amine - compound in which one or more hydrogen atom in ammonia is replaced by an organic functional group

amino acid - an organic acid containing a carboxyl (-COOH) and amine (-NH2) functional group along with a side chain

amorphous - term describing a solid that does not have crystalline structure

amphiprotic - species that can both accept and donate a proton or hydrogen ion

amphoteric - substance capable of acting as either an acid or a base

amphoteric oxide - oxide that can act as either an acid or a base in a reaction to produce a salt and water

Amplification: a technique, usually using enzymes, for multiplying nucleic acids in order to increase the sensitivity of detection methods

amu - atomic mass unit or 1/12th the mass of an unbound atom of carbon-12

analysis (mathematical analysis): grounded in the rigorous formulation of calculus, analysis is the branch of pure mathematics concerned with the notion of a limit (whether of a sequence or of a function)

analytic (Cartesian) geometry: the study of geometry using a coordinate system and the principles of algebra and analysis, thus defining geometrical shapes in a numerical way and extracting numerical information from that representation

analytical chemistry - chemistry discipline that studies the chemical composition of materials and tools used to examine them

Angle – Created by two rays and containing an endpoint in common

Angle Bisector: The line dividing an angle into two equal angles

Angle: Two rays sharing the same endpoint (called the angle vertex)

angstrom - unit of length equal to 10-10 meters

angular momentum quantum number - ℓ, the quantum number associated with the angular momentum of an electron

anhydrous - describes a substance that does not contain water or else is as concentrated as it can get

anion - an ion with a negative electrical charge

anode - electron where oxidation occurs; positive charged anode

Antibiotic resistance: a microorganism’s natural ability to withstand the effects of antibiotics: taking an antibiotic puts selective pressure on bacteria, eliminating bacteria that are susceptible to the antibiotic and selecting resistant bacteria, which then multiply

Antibiotic susceptibility testing: determines the growth of a bacterium in the presence of antibiotics and classifies it as susceptible, resistant or intermediate

Antibiotic: a substance of natural or synthetic origin capable of stopping the multiplication of bacteria

Antibody: a molecule produced by the immune system to detect and neutralize pathogens, in particular viruses

antibonding orbital - molecular orbital with an electron outside the region between the two nuclei

Antigens: a foreign substance in an organism which triggers the production of an antibody (immune reaction)

anti-Markovnikov addition - an addition reaction between an electrophilic compound HX and either an alkene or alkyne in which the hydrogen atom bonds to the carbon with the least number of hydrogen atoms and X bonds to the other carbon

antimony - Antimony is the name for the element with atomic number 36 and is represented by the symbol Kr It is a member of the metalloid group

anti-periplanar - periplanar conformation where the dihedral atom between atoms is between 150° and 180°

aqua regia - mixture of hydrochloric and nitric acids, capable of dissolving gold, platinum, and palladium

aqueous - describes a system containing water

aqueous solution - a solution in which water is the solvent

Arc – A set of points that lie on a circle and that are positioned within a central angle

Area – The space contained within a shape

Area: The two-dimensional space taken up by an object or shape, given in square units

argon - Argon is the name for the element with atomic number 18 and is represented by the symbol Ar It is a member of the noble gases group

arithmetic: the part of mathematics that studies quantity, especially as the result of combining numbers (as opposed to variables) using the traditional operations of addition, subtraction, multiplication and division (the more advanced manipulation of numbers is usually known as number theory)

aromatic compound - an organic molecule that contains a benzene ring

Array: A set of numbers or objects that follow a specific pattern

Arrhenius acid - species that dissociates in water to form protons or hydrogen ions

Arrhenius base - species that increases the number of hydroxide ions when added to water

arsenic - metalloid with element symbol As and atomic number 33

aryl - a functional group derived from a simple aromatic ring when one hydrogen is removed from the ring

associative property: property (which applies both to multiplication and addition) by which numbers can be added or multiplied in any order and still yield the same value, e.g (a + b) + c = a + (b + c) or (ab)c = a(bc)

astatine - Astatine is the name for the element with atomic number 85 and is represented by the symbol At It is a member of the halogen group

asymptote: a line that the curve of a function tends towards as the independent variable of the curve approaches some limit (usually infinity) i.e the distance between the curve and the line approaches zero

atmosphere - surrounding gases, such as the gases surrounding a planet that are held in place by gravity

atom - the defining unit of an element, which cannot be subdivided using chemical means

atomic mass - average mass of atoms of an element

atomic mass unit (amu) - 1/12th the mass of an unbound atom of carbon-12, used to represent atomic and molecular masses

atomic number - the number of protons in the nucleus of an atom of an element

atomic radius - value used to describe the size of an atom, usually half the distance between two atoms just touching each other

atomic solid - solid in which atoms are bonded to other atoms of the same type

atomic volume - volume occupied by one mole of an element at room temperature

atomic weight - average mass of atoms of an element

ATP - ATP is the acronym for the molecule adenosine triphosphate

Attribute: A characteristic or feature of an object—such as size, shape, color, etc.—that allows it to be grouped

Aufbau principle - idea that electrons are added to orbitals as protons are added to an atom

austenite - the face-centered cubic crystalline form of iron

Average – The numerical result of dividing the sum of two or more quantities by the number of quantities.

Average: The average is the same as the mean Add up a series of numbers and divide the sum by the total number of values to find the average

Avogadro's Law - relation that states equal volumes of all gases contain the same number of molecules at the same pressure and temperature

Avogadro's number - the number of particles in one mole of a substance; 6.0221 x 1023

axiom: a proposition that is not actually proved or demonstrated, but is considered to be self-evident and universally accepted as a starting point for deducing and inferring other truths and theorems, without any need of proof

azeotrope - a solution that retains its chemical composition when distilled

azimuthal quantum number - the quantum number associated with the angular momentum of an electron, determining the shape of its orbital

back titration - titration in which the analyte concentration is determined by reacting it with a known quantity of excess reagent

background radiation - radiation from external sources, typically from cosmic radiation and radioisotope decay

Bacterium: a unicellular microorganism lacking chlorophyll and visible only under a microscope Bacteria do not belong to either the plant or the animal kingdom

balanced equation - chemical equation in which the number and type of atoms and the electric charge is the same on both the reactant and product sides of the equation

Balmer series - the part of the hydrogen emission spectrum for electron transitions n=2 and n>2, There are four lines in the visible spectrum

Bar Graph: A graph that represents data visually using bars of different heights or lengths

barium - alkaline earth metal with element symbol Ba and atomic number 56

barometer - instrument used to measure atmospheric pressure

base - chemical species that either accepts protons or else donates electrons or hydroxide ions

Base 10: Number system that assigns place value to numbers

base anhydride (basic anhydride) - a metal oxide formed from the reaction between water and a basic solution

base metal - any metal besides a precious or noble metal used for jewelry or in industry

base n: the number of unique digits (including zero) that a positional numeral system uses to represent numbers, e.g base 10 (decimal) uses 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 in each place value position; base 2 (binary) uses just 0 and 1; base 60 (sexagesimal, as used in ancient Mesopotamia) uses all the numbers from 0 to 59; etc

Base: The bottom of a shape or three-dimensional object, what an object rests on

basic - alkaline or having a pH > 7

basic solution - aqueous solution containing more hydroxide ions than hydrogen ions; solution with pH > 7

Bayesian probability: a popular interpretation of probability which evaluates the probability of a hypothesis by specifying some prior probability, and then updating in the light of new relevant data

BEDMAS or PEMDAS Definition: An acronym used to help people remember the correct order of operations for solving algebraic equations BEDMAS stands for "Brackets, Exponents, Division, Multiplication, Addition, and Subtraction" and PEMDAS stands for "Parentheses, Exponents, Multiplication, Division, Addition, and Subtraction"

Beer's law (Beer-Lambert Law) - law that states the concentration of a solution is directly proportional to its light absorbance

Bell Curve: The bell shape created when a line is plotted using data points for an item that meets the criteria of normal distribution The center of a bell curve contains the highest value points

bell curve: the shape of the graph that indicates a normal distribution in probability and statistics

berkelium - radioactive metal with element symbol Bk and atomic number 97

beryllium - alkaline earth metal with element symbol Be and atomic number 4

beta decay - type of radioactive decay that results in spontaneous emission of a beta particle

beta particle - an electron or positron emitted during beta decay

beta radiation - ionizing radiation from beta decay in the form of an energetic electron or positron

bijection: a one-to-one comparison or correspondence of the members of two sets, so that there are no unmapped elements in either set, which are therefore of the same size and cardinality

binary acid - an acidic binary compound in which one element is hydrogen and the other element is another nonmetal

binary compound - a compound made up of two elements (e.g., HF)

binding energy - energy needed to remove an electron from an atom or to separate a proton or neutron from the atomic nucleus

Binomial – An expression in algebra that consists of two terms

binomial coefficients: the coefficients of the polynomial expansion of a binomial power of the form (x + y) n, which can be arranged geometrically according to the binomioal theorem as a symmetrical triangle of numbers known as Pascal’s Triangle, e.g (x + y)4 = x4 + 4x3y + 6x2y2 + 4xy3 + y4 the coefficients are 1, 4, 6, 4, 1

binomial: a polynomial algebraic expression or equation with just two terms, e.g 2x3 – 3y = 7; x2 + 4x; etc

Binomial: A polynomial equation with two terms usually joined by a plus or minus sign

biochemistry - Biochemistry is the chemistry of living things

Biochemistry: an area of science which studies the correlation between the structure of natural molecules and the consequences for their activity

Biomarker / marker: any indicator (nucleic acid, enzyme, metabolite and other types of molecules: histamines, hormones, proteins, etc.) present in the body or excreted by it as a biological response to a physiological or pathological

Bisect – To divide into two equal sections

bismuth - Bismuth is the name for the element with atomic number 83 and is represented by the symbol Bi It is a member of the metal group

bitumen - natural mixture of polycyclic aromatic hydrocarbons (PAHs)

black light - a lamp that emits ultraviolet radiation or the invisible radiation emitted by it

block copolymer - copolymer formed by repeating monomer subunits

Blood culture: laboratory analysis used to detect bloodstream infections, carried out by taking a sample of venous blood, which is then cultured to reveal the presence or absence of pathogenic microbes

bohrium - transition metal with element symbol Bh and atomic number 107

boiling - phase transition from the liquid to gas state

Boiling occurs when the vapor pressure of a liquid exceeds atmospheric pressure

boiling point - temperature at which a liquid's vapor pressure is equal to the external gas pressure

boiling point elevation - the increase in a liquid boiling point caused by adding another compound to it

bond - a chemical link formed between atoms in molecules and molecules and ions in crystals

bond angle - the angle formed between two adjacent chemical bonds within the same atom

bond energy - quantity of energy needed to break one mole of molecules into component atoms

bond enthalpy - enthalpy change resulting when one mole of bonds in a species are broken at 298 K

bond length - the equilibrium distance between atomic nuclei or groups of nuclei that share a chemical bond

bond order - a measure of the number of electrons involved in chemical bonds between two atoms in a molecule; usually equal to the number of bonds between the atoms

bond-dissociation energy - energy required to homolytically break a chemical bond

Boolean algebra or logic: a type of algebra which can be applied to the solution of logical problems and mathematical functions, in which the variables are logical rather than numerical, and in which the only operators are AND, OR and NOT

boron - Boron is the name for the element with atomic number 5 and is represented by the symbol B It is a member of the semimetal group

Box and Whisker Plot/Chart: A graphical representation of data that shows differences in distributions and plots data set ranges

Boyle's law - ideal gas law that states the volume of a gas is inversely proportional to its absolute pressure, assuming constant temperature

branched chain alkane - an alkane with alkyl groups bonded to the central carbon chain The molecules are branched, but all C-C bonds are single bonds

brass - Brass is defined as an alloy of copper and zinc

bromine - Bromine is the name for the element with atomic number 35 and is represented by the symbol Br It is a member of the halogen group

Bronsted-Lowry acid - species that yields hydrogen ions

Bronsted-Lowry base - species that accepts hydrogen ions in a reaction

bronze - Bronze is an alloy of copper, usually containing tin as its main addition

buffer - either a weak acid and its salt or else a weak base and its salt that form an aqueous solution that resists pH changes

cadmium - Cadmium is the name for the element with atomic number 48 and is represented by the symbol Cd It is a member of the transition metals group

caffeine - Caffeine is a chemical substance naturally found in tea and coffee and added to colas

calcium - Calcium is the name for the element with atomic number 20 and is represented by the symbol Ca It is a member of the alkaline earth metal group

calculus (infinitesimal calculus): a branch of mathematics involving derivatives and integrals, used to study motion and changing values

calculus of variations: an extension of calculus used to search for a function which minimizes a certain functional (a functional is a function of a function)

Calculus: The branch of mathematics involving derivatives and integrals, Calculus is the study of motion in which changing values are studied

calorie - unit of thermal energy; the amount of energy required to raise the temperature of 1 gram of water 1 degree C or K at standard pressure

calorimeter - instrument designed to measure heat flow of a chemical reaction or physical change

Campylobacter: a genus of Gram-negative bacteria that can cause food poisoning

Canceling – In multiplication of fractions, when one number is divided into both a numerator and a denominator

Candida albicans: the most important and best-known yeast species of the Candida genus It causes infections (candidiasis), mainly of the digestive and vaginal mucosa

Capacity: The volume of substance that a container will hold

capillary action - the spontaneous floe of liquid into a narrow tube or porous material

Carbapenemases: b-lactamase type enzymes which hydrolyze carbapenems, a class of antibiotics with extended-spectrum activity, mainly used for the treatment of multi-drug resistant bacterial infections

carbon - Carbon is the name for the element with atomic number 6 and is represented by the symbol C It is a member of the nonmetal group

carbonate - an ion consisting of one carbon bonded to three oxygen atoms (CO32-) or a compound containing this ion

carbonyl - functional group consisting of a carbon atom double bonded to oxygen, C=O

carboxyl group - functional group consisting of a carbon double bonded to oxygen and single bonded to a hydroxyl (-COOH)

cardinal numbers: numbers used to measure the cardinality or size (but not the order) of sets – the cardinality of a finite set is just a natural number indicating the number of elements in the set; the sizes of infinite sets are described by transfinite cardinal numbers, 0 (aleph-null), 1 (aleph-one), etc

Cartesian coordinates – Ordered number pairs that are assigned to points on a plane

Cartesian coordinates: a pair of numerical coordinates which specify the position of a point on a plane based on its distance from the the two fixed perpendicular axes (which, with their positive and negative values, split the plane up into four quadrants)

catalyst - substance that increases the chemical reaction rate by decreasing its activation energy

catenation - binding of an element to itself via covalent bonds, forming a chain or ring

cathode - electrode where reduction occurs; usually the negative electrode

cathode ray tube - a vacuum tube with a source of electrons, a fluorescent screen, and means of accelerating and deflecting the electron beam

cation - ion with a positive electrical charge

Celsius temperature scale - temperature scale where 0°C and 100°C are defined as the freezing and boiling points of water, respectively

Centimeter: A metric unit of measurement for length, abbreviated as cm 2.5 cm is approximately equal to an inch

cerium - rare earth metal with element symbol Ce and atomic number 58

cesium - Cesium is the name for the element with atomic number 55 and is represented by the symbol Cs It is a member of the alkali metal group

cetane number (CN) - value that describes the combustion quality of diesel fuel, based on the delay between injection and ignition

chain reaction - set of chemical reactions in which products become reactants of another reaction

charge - an electrical charge, a conserved property of subatomic particles determining their electromagnetic interaction

Charles's law - ideal gas law that states the volume of an ideal gas is directly proportional to absolute temperature, assuming constant pressure

chelate - organic compound formed by bonding a polydentate ligand to a central metal atom, or the act of forming such a compound

chemical - any matter or substance that has mass

chemical change - process by which one or more substances are altered to form new substances

chemical energy - energy contained in the internal structure of an atom or molecule

chemical equation - description of a chemical reaction, including the reactants, products, and direction of the reaction

chemical equilibrium - state of a chemical reaction where the concentration of the reactants and products remains stable over time

chemical formula - expression which states the number and type of atoms in a molecule

chemical kinetics - the study of chemical processes and rates of reactions

chemical property - characteristic which may be observed when matter undergoes a chemical change

chemical reaction - a chemical change in which reactants form one or more new products

chemical symbol - one- or two-letter representation of a chemical element (e.g., H, Al)

chemiluminescence - light emitted as a result of a chemical reaction

chemistry - study of matter and energy and the interactions between them

Chemistry Definitions Starting With the Letter J

Cherenkov radiation - Cherenkov radiation is the electromagnetic radiation emitted when a charged particle moves through a dielectric medium faster than the velocity of light in the medium

chiral center - the atom in a molecule bonded to four chemical species, allowing optical isomerism

chirality - Chirality or chiral describes a nonsuperimposable mirror image, like left and right hands Usually in chemistry the term is used to describe a pair of molecules that have the same formulas, but form a pair of structures

chlorine - halogen with atomic number 17 and element symbol Cl

chlorofluorocarbon - A chlorofluorocarbon or CFC is a compound that contains atoms of chlorine, fluorine, and carbon

Chord – A line segment that connects two points on a circle.

Chord: A segment joining two points on a circle

chromatography - group of techniques used to separate mixture components by passing the mixture through a stationary phase

chromium - Chromium is the name for the element with atomic number 24 and is represented by the symbol Cr It is a member of the transition metals group

Chromogen: molecule that gives off a color under certain conditions When incorporated into a culture medium, it reveals the presence of an enzyme specific to a given bacteria, thereby indicating the bacteria that is cultured

Circle – A set of points that are all the same distance from a given point.

Circumference – The distance measured around a circle.

Circumference: The complete distance around a circle or a square

closed system - thermodynamic system in which mass is conserved within the system, but energy can freely enter or exit

coagulation - the gelling or clumping of particles, usually in a colloid

cobalt - transition metal that is atomic number 27 with element symbol Co

Coefficient – A number that is placed in front of a variable. For example, in 6x, 6 is the coefficient.

Coefficient: A letter or number representing a numerical quantity attached to a term (usually at the beginning) For example, x is the coefficient in the expression x(a + b) and 3 is the coefficient in the term 3y

coefficients: the factors of the terms (i.e the numbers in front of the letters) in a mathematical expression or equation, e.g in the expression 4x + 5y2 + 3z, the coefficients for x, y2 and z are 4, 5 and 3 respectively

coenzyme - substance that works with an enzyme to aid its function or initiate its action

cohesion - measure of how well molecules stick to each other or group together

collagen - an important family of proteins found in humans and other animals, found in skin, cartilage, blood vessels, and tendons

colligative properties - properties of a solution that depend on the number of particles in a volume of solvent

colloid - a homogenous mixture in which dispersed particles do not settle out

combination reaction - reaction in which two reactants combine to form a single product

combinatorics: the study of different combinations and groupings of numbers, often used in probability and statistics, as well as in scheduling problems and Sudoku puzzles

combined gas law - law which states the ratio of the product of pressure and volume, divided by the absolute temperature, is a constant value

combustion - chemical reaction between a fuel and oxidizer that yields energy (usually heat and light)

Commensal bacteria: the skin and mucous membranes are continuously colonized by commensal bacteria that do not cause disease unless the subject is weakened

Common denominator – A number that can be divided evenly by all denominators in the problem

Common Factors: A factor shared by two or more numbers, common factors are numbers that divide exactly into two different numbers

common-ion effect - suppressing effect an electrolyte has on the ionization of another electrolyte that shares a common ion

Complementary angles – Two angles in which the sum of their measurements equals 90°.

Complementary Angles: Two angles that together equal 90°

complex dynamics: the study of mathematical models and dynamical systems defined by iteration of functions on complex number spaces

Complex fraction – A fraction that contains a fraction or fractions in the numerator and/or denominator

complex ion - ion in which a central metal ion is bonded to one or more ions or molecules

complex number: a number expressed as an ordered pair comprising a real number and an imaginary number, written in the form a + bi, where a and b are real numbers, and i is the imaginary unit (equal to the square root of -1)

composite number: a number with at least one other factor besides itself and one, i.e not a prime number

Composite Number: A positive integer with at least one factor aside from its own Composite numbers cannot be prime because they can be divided exactly

compound - chemical species formed when two or more atoms form a chemical bond

concentrated - having a large ratio of solute to solvent

concentration - an expression of the quantity of a substance in a defined volume

condensation - state of matter change from vapor phase to liquid phase

condensation reaction - chemical reaction in which one of the products is water or ammonia, also known as a dehydration reaction

condensed formula - chemical formula in which atom symbols are listed in the order they appear in the molecular structure, with limited bond dashes

conductor - material which permits the flow of energy (e.g., electrical conductor, thermal conductor)

Cone: A three-dimensional shape with only one vertex and a circular base

conformer - an isomer that differs from another isomer by rotation around a single bond

congener - member of the same group of elements of the periodic table (e.g., iodine and chlorine)

congruence: two geometrical figures are congruent to one another if they have the same size and shape, and so one can be transformed into the other by a combination of translation, rotation and reflection

Congruent – Exactly the same Identical in regard to size and shape

Congruent: Objects and figures that have the same size and shape Congruent shapes can be turned into one another with a flip, rotation, or turn

Conic Section: The section formed by the intersection of a plane and cone

conic section: the section or curve formed by the intersection of a plane and a cone (or conical surface), depending on the angle of the plane it could be an ellipse, a hyperbola or a parabola

conjugate - multiple chemistry definitions, referring to Bronsted acids and bases, a compound formed by combining other compounds, or the overlap of p-orbitals across a sigma bond

conjugate acid - HX, a compound differing from a base X by a proton

conjugate base - the species that gains a proton in an acid-base reaction

conservation of energy - law which states energy can change forms but may not be created or destroyed

conservation of mass - law that states, in a closed system, matter can change forms but not be created or destroyed

Constant: A value that does not change

Consumable: a single-use accessory, generally employed in an analysis instrument

Contaminant: a substance present where it should not be

continued fraction: a fraction whose denominator contains a fraction, whose denominator in turn contains a fraction, etc, etc

controlled variable - variable that a scientist holds constant in an experiment; the control or constant variable

conversion factor - numerical ratio that converts a measurement from one unit into another

coordinate bond - covalent bond between two atoms in which one atom supplies both electrons for the bond

Coordinate graph – Two perpendicular number lines, the x axis and the y axis, which make a plane upon which each point is assigned a pair of numbers

coordinate plane: a plane with two scaled perpendicular lines that intersect at the origin, usually designated x (horizontal axis) and y (vertical axis)

Coordinate: The ordered pair that gives a precise location or position on a coordinate plane

coordinate: the ordered pair that gives the location or position of a point on a coordinate plane, determined by the point’s distance from the x and y axes, e.g (2, 3.7) or (-5, 4)

coordination compound - compound containing one or more coordinate bonds

coordination number - number of atoms bonded to a central atom

copernicium - radioactive element with symbol Cn and atomic number 112

copper - Copper is the name for the element with atomic number 29 and is represented by the symbol Cu It is a member of the transition metals group

correlation: a measure of relationship between two variables or sets of data, a positive correlation coefficient indicating that one variable tends to increase or decrease as the other does, and a negative correlation coefficient indicating that one variable tends to increase as the other decreases and vice versa

corrosion - irreversible damage to a material or tissue due to a chemical reaction

corrosive - having the power to cause irreversible chemical damage upon contact

Corynebacterium: a genus of bacteria including many species of Gram-positive bacilli which account for a large proportion of the flora of the skin and of the mucosa

Cosine: In a right triangle, cosine is a ratio that represents the length of a side adjacent to an acute angle to the length of the hypotenuse

Coulomb's law - law which states the force between two charges is proportional to the quantity of both charges and inversely proportional to the square of the distance between them

covalent bond - chemical link between atoms or ions in which the electron pairs are more or less evenly shared between them

covalent compound - molecule that contains covalent chemical bonds

covalent radius - half the diameter of the part of an atom that participates in a covalent bond

crenation - forming a scalloped shape upon exposure to a hypertonic solution

critical point - critical state; point at which two phases of matter become indistinguishable from one another

crystal - matter in which atoms, ions, or molecules are packed into an ordered, repeating three-dimensional pattern

crystal field splitting - the difference in energy between the d orbitals of ligands

crystallize - solidification of matter into the highly ordered form of a crystal

Cube – A solid with six sides, with the sides being equal squares and the edges being equal Also, the resulting number when a number is multiplied by itself twice

Cube root – A number that when multiplied by itself twice gives the original number. For example, 4 is the cube root of 64.

cubic equation: a polynomial having a degree of 3 (i.e the highest power is 3), of the form ax3 + bx2 + cx + d = 0, which can be solved by factorization or formula to find its three roots

Culture medium: a simple or complex nutrient composition in liquid or solid form, used to maintain or increase the development of a microbial species under appropriate biological conditions

curium - radioactive metal with element symbol Cm and atomic number 96

current - rate of flow of electricity

Cylinder: A three-dimensional shape featuring two circle bases connected by a curved tube

cyrogenics - study of matter at extremely low temperatures

Cytology (or cellular biology): an area of biology concerning the study of cells and their organelles, the vital processes taking place therein as well as the mechanisms allowing for their survival (reproduction, metabolism)

Cytomegalovirus: a virus responsible for infections, usually undetected It becomes pathogenic especially in patients with weak immune defenses Member of the herpes virus family, which includes inter alia herpes simplex virus (HSV) or herpes virus hominis (HVH), cytomegalovirus (CMV), varicellazoster virus (VZV) and Epstein-Barr virus (EBV)

Cytometry: the counting of cells

Dalton's Law - relation stating the total pressure of a gaseous mixture equals the sum of the partial pressure of the component gases

darmstadtium - Darmstadtium is the name for the element with atomic number 110 and is represented by the symbol Ds Darmstadtium was formerly known as ununnilium with symbol Uun It is a member of the transition metals group

dative bond - covalent bond between atoms in which one atom provides both electrons for the bond

daughter isotope - product formed after a radioisotope (the parent) undergoes radioactive decay

de Broglie Equation - equation describing the wave properties of matter, stated as wavelength equals Planck's constant divided by the product of mass and velocity

Decagon: A polygon/shape with ten angles and ten straight lines

decantation - method of separating mixtures by removing the liquid layer from a precipitate

Decimal fraction – Fraction with a denominator of 10, 100, 1,000, etc., written using a decimal point

decimal number: a real number which expresses fractions on the base 10 standard numbering system using place value, e.g 37⁄100 = 0.37

Decimal: A real number on the base ten standard numbering system

decomposition reaction - chemical reaction in which a single reactant yields two or more products

deductive reasoning or logic: a type of reasoning where the truth of a conclusion necessarily follows from, or is a logical consequence of, the truth of the premises (as opposed to inductive reasoning)

deflagration - type of combustion in which flame propagation is less than 100 m/s and overpressure is less than 0.5 bar

Degree – The measurement unit of an angle

Degree: The unit of an angle's measure represented with the symbol °

dehydration reaction - chemical reaction between two compounds in which one of the products is water

deliquescence - process by which a soluble substance picks up water vapor from the atmosphere to form a solution

delocalized electron - any electron in an ion, atom, or molecule that is no longer associated with a particular atom or single covalent bond

Denominator – The bottom symbol or number of a fraction

Denominator: The bottom number of a fraction The denominator is the total number of equal parts into which the numerator is being divided

density - mass per unit volume

dependent variable - variable being measured (tested) in response to changing the independent variable

deposition - settling of sediment or particles onto a surface or the phase change from the vapor to solid phase

deprotonation - chemical reaction in which a radical removes a proton from a molecule

derivative: a measure of how a function or curve changes as its input changes, i.e the best linear approximation of the function at a particular input value, as represented by the slope of the tangent line to the graph of the function at that point, found by the operation of differentiation

derived unit - an SI unit made from a combination of the base units (e.g., Newton is kg·m/s2)

descriptive geometry: a method of representing three-dimensional objects by projections on the two-dimensional plane using a specific set of procedures

desiccant - chemical agent that picks up water, often used for drying

desublimation - phase change from vapor to solid

detergent - cleaning agent with general structure R-SO4-, Na+, where R is a long-chain alkyl group

Diagonal: A line segment that connects two vertices in a polygon

diamagnetic - not attracted to a magnetic field, generally because the material does not contain unpaired electrons

Diameter – A line segment that contains the center and has its endpoints on the circle Also, the length of this segment

Diameter: A line that passes through the center of a circle and divides it in half

Difference – That which results from subtraction.

Difference: The difference is the answer to a subtraction problem, in which one number is taken away from another

differential equation: an equation that expresses a relationship between a function and its derivative, the solution of which is not a single value but a function (has many applications in engineering, physics economics, etc)

differential geometry: a field of mathematics that uses the methods of differential and integral calculus (as well as linear and multilinear algebra) to study the geometry of curves and surfaces

differentiation: the operation in calculus (inverse to the operation of integration) of finding the derivative of a function or equation

diffusion - movement of a fluid from a region of higher concentration to lower concentration

Digit: Digits are the numerals 0-9 found in all numbers 176 is a 3-digit number featuring the digits 1, 7, and 6

dilute - solution containing a small amount of solute relative to the amount of solvent

Diophantine equation: a polynomial equation with integer coefficients that also allows the variables and solutions to be integers only

dipole - a separation of electrical or magnetic charges

dipole moment - measure of the separation of two opposite electrical charges

diprotic acid - acid that can donate two hydrogen atoms or protons per molecule in an aqueous solution

direct proportion - relation between two variables such that their ratio is a constant value

disaccharide - carbohydrate formed when two monosaccharides bond, removing a molecule of water from their structure

displacement reaction - chemical reaction in which the cation or anion of one reactant is replaced by one from another reactant

disproportionation - chemical reaction (usually redox) where a molecule forms two or more dissimilar products

dissociation reaction - chemical reaction in which a reactant breaks into two or more parts

dissolve - a solute passing into solution, usually a solid going to the liquid phase

distillate - vapor formed by a distillation, which may be condensed into a liquid for collection

distillation - technique of heating a liquid to form a vapor, which is cooled to separate components of the liquid based on volatility or boilings

distributive property: property whereby summing two numbers and then multiplying by another number yields the same value as multiplying both values by the other value and then adding them together, e.g a(b + c) = ab + ac

divalent cation - positive charged ion with a valence of 2

Dividend: A number being divided into equal parts (inside the bracket in long division)

Divisor: A number that divides another number into equal parts (outside of the bracket in long division)

DNA - deoxyribonucleic acd, an organic molecule that codes for proteins

DNA sequencing: method used to determine the order of the nucleotide bases for a given DNA fragment

DNA: the acronym of "Deoxyribonucleic Acid" These nucleotides consist of a sugar (deoxyribose), a phosphate group and one of the following nitrogen-containing bases: adenine (A), cytosine (C), guanine (G) or thymine (T), and serve as a medium for genetic information

double bond - chemical bond in which two electron pairs are shared between two atoms

double replacement reaction - chemical reaction in which two reactants exchange anions/cations to form two new products using the same ions

Dry ice is the name for solid carbon dioxide

dubnium - transition metal with element symbol Db and atomic number 105

ductile - able to be stretched into a wire without breaking

dynamic equilibrium - chemical equilibrium between the forward and reverse reaction in which the rates of reaction are equal to each other

dysprosium - rare earth metal with element symbol Dy and atomic number 66

Edge: A line is where two faces meet in a three-dimensional structure

effective nuclear charge - net charge an electron experiences in an atom that has multiple electrons

effervescence - foaming or bubbling when gas is evolved by a liquid or solid

efflorescence - process by which a hydrate loses water of hydration

effusion - movement of gas through a pore or capillary into a vacuum or another gas

einsteinium - Einsteinium is the name for the element with atomic number 99 and is represented by the symbol Es It is a member of the actinide group

elasticity - physical property of matter describing the ability to return to original shape after deformation

electrical conductivity - measure of a substance's ability to carry an electrical current

electrical resistivity - measure of how much a material resists carrying an electrical current

electrochemical cell - device that generates a potential difference between electrodes via chemical reactions

electrochemistry - scientific study of reactions and species formed at the interface between an electrolyte and a conductor, where electron transfer occurs

electrode - the anode or cathode of an electrical cell

electrolysis - passage of direct current through an ion-conducting solution, producing a chemical change at the electrodes

electrolyte - a substance that forms ions in aqueous solution

electrolytic cell - type of electrochemical cell in which the flow of electric energy from an external source enables a redox reaction

electromagnetic radiation - light; self propagating energy that has electric and magnetic field components

electromotive force - emf - the electric potential generated by either an en electrochemical cell or changing magnetic field

electron - stable negatively charged subatomic particle

electron affinity - measure of the ability of an atom to accept an electron

electron capture (EC) - form of radioactive decay in which the atomic nucleus absorbs a K or L shell electron, converting a proton into a neutron

electron cloud - region of negative charge surrounding the atomic nucleus that has a high probability of containing electrons

electron configuration - description of the population of the electronic energy sublevels of an atom

electron density - representation of the probability of finding an electron in a specific region around an atom or molecule

electron domain - the number of lone electron pairs or bond locations around an atom or molecule

electron pair repulsion - principle that electron pairs surrounding a central atom orient themselves as far apart as possible; used to predict geometry

electron spin - property of an electron related to its spin about an axis, described by a quantum number as either +1/2 or -1/2

electronegativity - property of an atom that reflects its ability to attract electrons in a chemical bond

Electrons are particles with negative charge that orbit the atomic nucleus

electron-sea model - model of metallic bonding in which cations are described as fixed points in a mobile sea of electrons

electrophile - atom or molecule that accepts an electron pair to form a covalent bond

electroplating - process of adding a metal coat to a material by using a reduction reaction

electrostatic forces - forces between particles due to their electrostatic charges

electrum - a natural alloy of gold and silver

element - a substance that cannot be subdivided using chemical means; identified by the number of protons in its atoms

element symbol - the one- or two-letter abbreviation of a chemical element (e.g., H, Cl)

element: a member of, or an object in, a set

elementary reaction - chemical reaction in which reactants form products in a single step without a transition state

ellipse: a plane curve resulting from the intersection of a cone by a plane, that looks like a slightly flattened circle (a circle is a special case of an ellipse)

Ellipse: An ellipse looks like a slightly flattened circle and is also known as a plane curve Planetary orbits take the form of ellipses

elliptic geometry: a non-Euclidean geometry based (at its simplest) on a spherical plane, in which there are no parallel lines and the angles of a triangle sum to more than 180°

emission spectrum - range of wavelengths emitted by an atom stimulated by electricity or heat

emissions - products of a combustion reaction, aside from heat and light (e.g., carbon dioxide)

empirical formula - formula that shows the ratio of elements in a compound, but not necessarily their actual numbers in a molecule

empty (null) set: a set that has no members, and therefore has zero size, usually represented by {} or ø

emulsifier - stabilizing agent that prevents immiscible liquids from separating

emulsion - colloid formed from two or more immiscible liquids where one liquid contains a dispersion of the other liquid(s)

enantiomer - a member of a pair of optical isomers

End Point: The "point" at which a line or curve ends

endothermic - process which absorbs thermal energy from its environment

Endotoxin: component of the outer membrane of certain Gram-negative bacteria that can cause high fevers

enediol - an alkene enol with a hydroxyl group attached to both carbon atoms of the C=C bond

energy - the ability to do work (e.g., kinetic energy, light)

Enterobacteria: a family of bacilli (bacteria) revealed by Gram-negative staining which are aerobic or anaerobic (they can live and reproduce with or without oxygen)

Enterococcus: oval-shaped bacterium of the group D of the Streptococcus family, usually resident in the intestine of healthy humans

enthalpy - thermodynamic property of a system that is the sum of the internal energy and the product of pressure and volume

enthalpy change - the energy change of a system at constant pressure

enthalpy of atomization - quantity of enthalpy change when chemical bonds are broken in a compound to form individual atoms

enthalpy of reaction - difference between total enthalpy of products and total enthalpy of reactants of a chemical reaction

entropy - measure of the disorder of a system

Enumeration: counting how many microbes (bacteria or fungi) are present in a sample

enzyme - An enzyme is a protein that functions as a catalyst for a chemical reaction

Enzyme: a protein macromolecule which speeds up a biochemical reaction

Equation – A relationship between symbols and/or numbers that is balanced.

Equation: A statement that shows the equality of two expressions by joining them with an equals sign

Equilateral triangle – A triangle that has three equal angles and three sides the same length.

Equilateral: A term used to describe a shape whose sides are all of equal length

equilibrium constant - ratio of the equilibrium concentration of products raised to the power of their stoichiometric coefficients to the equilibrium concentration of the reactants raised to the power of their stoichiometric coefficients

equivalence point - point in a titration where the titrant completely neutralizes the analyte

erbium - Erbium is element atomic number 68 on the periodic table

essential amino acid - amino acid needed in the diet because an organism cannot synthesize it

ester - RCO2R′, where R is the hydrocarbon parts of the carboxylic acid and R′ is the alcohol

ether - organic compound containing two aryl or alkyl groups bound to an oxygen, R-O-R'

Euclidean geometry: “normal” geometry based on a flat plane, in which there are parallel lines and the angles of a triangle sum to 180°

europium - Europium is the name for the element with atomic number 63 and is represented by the symbol Eu It is a member of the lanthanide group

eutectic - homogeneous solid mixture of at least two types of atoms or molecules that form a superlattice (usually a mix of alloys)

Evaluate: This word means "to calculate the numerical value"

evaporation - process characterized by a spontaneous transition of molecules from the liquid phase to vapor phase

Even number – An integer which can be divided by 2, with no remainder.

Even Number: A number that can be divided or is divisible by 2

Event: This term often refers to an outcome of probability; it may answers question about the probability of one scenario happening over another

excess reactant - reactant left over in a reaction because it is present in a great amount than needed to react with the limiting reactant

excited state - atom, ion, molecule, or subatomic particle in a higher energy level than its ground state

exergonic - releasing energy to its surroundings

exothermic - releasing energy to the environment in the form of heat; a type of exergonic process

exothermic reaction - a chemical reaction that releases heat

Expanded notation – To point out the place value of a digit by writing the number as the digit times its place value.

expected value: the amount predicted to be gained, using the calculation for average expected payoff, which can be calculated as the integral of a random variable with respect to its probability measure (the expected value may not actually be the most probable value and may not even exist, e.g 2.5 children)

Exponent – A positive or negative number that expresses the power to which the quantity is to be raised or lowered. It is placed above and to the right of the number.

Exponent: The number that denotes repeated multiplication of a term, shown as a superscript above that term The exponent of 34 is 4

exponentiation: the mathematical operation where a number (the base) is multiplied by itself a specified number of times (the exponent), usually written as a superscript an, where a is the base and n is the exponent, e.g 43 = 4 x 4 x 4

Expressions: Symbols that represent numbers or operations between numbers

Extended-spectrum beta-lactamase: beta-lactamases are a family of enzymes responsible for bacterial resistance to certain antibiotics such as penicillin

extensive property - property of matter that depends on the quantity of matter that is present (e.g., volume)

Exterior angle – In a triangle, an exterior angle i s equal to the measures of the two interior angles added together.

Extraction: term applied to the steps which extract nucleic acids from the cells that contain them and process them so they can be used in molecular biology techniques such as amplification

f orbital - electron orbital with l = 3 for the angular momentum quantum number,

F.O.I.L Method – A method used for multiplying binomials in which the first terms, the outside terms, the inside terms, and then the last terms are multiplied

Faraday constant - a physical constant equal to the electric charge of one mole of electrons, 96485.33 C/mol

Face: The flat surfaces on a three-dimensional object

Factor – As a noun, it is a number or symbol which divides evenly into a larger number As a verb, it means to find two or more values whose product equals the original value

Factor – As a noun, it is a number or symbol which divides evenly into a larger number. As a verb, it means to find two or more values whose product equals the original value.

Factor Tree: A graphical representation showing the factors of a specific number

Factor: A number that divides into another number exactly The factors of 10 are 1, 2, 5, and 10 (1 x 10, 2 x 5, 5 x 2, 10 x 1)

factor: a number that will divide into another number exactly, e.g the factors of 10 are 1, 2 and 5

Factorial Notation: Often used in combinatorics, factorial notations requires that you multiply a number by every number smaller than it The symbol used in factorial notation is ! When you see x!, the factorial of x is needed

factorial: the product of all the consecutive integers up to a given number (used to give the number of permutations of a set of objects), denoted by n!, e.g 5! = 1 x 2 x 3 x 4 x 5 = 120

Factoring: The process of breaking numbers down into all of their factors

family - a group of elements that share similar properties

fat - triesters of glycerol and fatty acids that are soluble in organic solvents, but generally insoluble in water

fatty acid - a carboxylic acid with a long hydrocarbon side chain

feedstock - any unprocessed material used as a supply for a manufacturing process

Fermat primes: prime numbers that are one more than a power of 2 (and where the exponent is itself a power of 2), e.g 3 (21 + 1), 5 (22 + 1), 17 (24 + 1), 257 (28 + 1), 65,537 (216 + 1), etc

fermium - Fermium is the name for the element with atomic number 100 and is represented by the symbol Fm It is a member of the actinide group

Fibonacci numbers (series): a set of numbers formed by adding the last two numbers to get the next in the series: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, …

Figure: Two-dimensional shapes

finite differences: a method of approximating the derivative or slope of a function using approximately equivalent difference quotients (the function difference divided by the point difference) for small differences

Finite: Not infinite; has an end

fire point - the lowest temperature a vapor will initiate and sustain combustion

first law of thermodynamics - law which states the total energy of a system and its surroundings is a constant value; the law of conservation of energy

fission - the splitting of an atomic nucleus, which results in two or more lighter nuclei and a release of energy

flame test - an analytical technique used to identify ions based on their emission spectrum in a flame

flammable - easily ignited or capable of sustained combustion

Flip: A reflection or mirror image of a two-dimensional shape

Flow cytometry: technique of passing a stream of cells, particles or molecules at high speed through a laser beam The light re-emitted (by diffusion or fluorescence) enables the population to be classified and sorted according to several criteria

fluid - a substance that flows under applied shear stress, including liquids, gases, and plasma

Fluids that don't mix are said to be immiscible

fluorescence - luminescence released when an atom absorbs electromagnetic radiation and emits a photon when the electron falls to a lower energy state

foam - a substance containing gas bubbles trapped within a liquid or solid

force - a push or pull on a mass, with both magnitude and direction (vector)

formal charge - the difference between the number of valence electrons of an atom and the number of electrons associated with the atom (e.g., in a chemical bond)

formation reaction - reaction in which one mole of a product is formed

formula mass or formula weight - the sum of the atomic weights of the atoms in a compound's empirical formula

formula: a rule or equation describing the relationship of two or more variables or quantities, e.g A = πr2

Formula: A rule that numerically describes the relationship between two or more variables

Fourier series: an approximation of more complex periodic functions (such as square or saw-tooth functions) by adding together various simple trigonometric functions (e.g sine, cosine, tangent, etc)

fractal: a self-similar geometric shape (one that appears similar at all levels of magnification) produced by an equation that undergoes repeated iterative steps or recursion

Fraction – A symbol which expresses part of a whole It contains a numerator and a denominator

Fraction – A symbol which expresses part of a whole. It contains a numerator and a denominator.

Fraction: A quantity that is not whole that contains a numerator and denominator The fraction representing half of 1 is written as 1/2

fraction: a way of writing rational numbers (numbers that are not whole numbers), also used to represent ratios or division, in the form of a numerator over a denominator, e.g 3⁄5 (a unit fraction is a fraction whose numerator is 1)

fractional distillation - process which separates components of a mixture according to their boiling points

francium - alkali metal with element symbol Fr and atomic number 87

free energy - the amount of internal energy of a system that is available to do work

free radical - an atom or molecule with an unpaired electron

freezing - process in which a liquid changes to a solid

freezing point - temperature at which a liquid transitions to a solid (not always the same as melting point)

freezing point depression - lowering the freezing point of a liquid by adding another compound to it

frequency - number of times a point on a wave passes a reference point in one second

Frequency: The number of times an event can happen in a given period of time; often used in probability calculations

function: a relation or correspondence between two sets in which one element of the second (codomain or range) set ƒ(x) is assigned to each element of the first (domain) set x, e.g ƒ(x) = x2 or y = x2 assigns a value to ƒ(x) or y based on the square of each value of x

functional groups or functional moiety - group of atoms in a molecule that are responsible for characteristic reactions and properties

Functionalized polymer: an organic or inorganic macromolecule formed by a chain of repeating units to which chemical groups are grafted in order to give the macromolecule a particular function

Fungal: that which relates to fungi

Furlong: A unit of measurement representing the side length of one square acre One furlong is approximately 1/8 of a mile, 201.17 meters, or 220 yards

fusion - combining light atomic nuclei to form a heavier nucleus, accompanied by the release of energy

gadolinium - rare earth metal with element symbol Gd and atomic number 64

gallium - metal with element symbol Ga and atomic number 31

galvanic cell - electrochemical cell where reactions between dissimilar conductors occur through a salt bridge and electrolyte

game theory: a branch of mathematics that attempts to mathematically capture behaviour in strategic situations, in which an individual’s success in making choices depends on the choices of others, with applications in the areas of economics, politics, biology, engineering, etc

gamma radiation - high energy ionizing photons, originating from the atomic nucleus

gas - state of matter characterized by having neither a defined shape nor defined volume

gas constant (R) - the constant in the Ideal Gas Law; R = 8.3145 J/mol·K

Gaussian curvature: an intrinsic measure of the curvature of a point on a surface, dependent only on how distances are measured on the surface and not on the way it is embedded in space

Gay-Lussac's law - form of the ideal gas law that states the pressure of an ideal gas is directly proportional to its absolute (Kelvin) temperature when volume is held constant

gel - a type of sol where the solid particles are held in a mesh to form a rigid or semi-rigid mixture

Genotyping: determination of all the genes contained in the cells of an organism

geometric isomer - molecules with the same number and type of atoms as each other, but with different geometrical configurations Also called cis-trans or configurational isomerism

geometry: the part of mathematics concerned with the size, shape and relative position of figures, or the study of lines, angles, shapes and their properties

Geometry: The study of lines, angles, shapes, and their properties Geometry studies physical shapes and the object dimensions

germanium - metalloid with element symbol Ge and atomic number 32

Gibbs free energy - a measure of the potential for reversible or maximum work done by a system at constant pressure and temperature

glass - an amorphous solid

glycosidic bond - a covalent bond between a carbohydrate and a functional group or another molecule

gold - yellow-colored transition metal with element symbol Au and atomic number 79

golden ratio (golden mean, divine proportion): the ratio of two quantities (equivalent to approximately 1 : 1.6180339887) where the ratio of the sum of the quantities to the larger quantity equals the ratio of the larger quantity to the smaller one, usually denoted by the Greek letter phi φ (phi)

Graham's Law - relation stating the rate of effusion of a gas is inversely proportional to the square root of its molecular mass or density

grain alcohol - purified form of ethyl alcohol made from distilling fermented grain

gram - unit of mass equal to the mass of one cubic centimeter of water at 4°C

gram molecular mass - the mass in grams of one mole of a molecular substance

Gram staining: staining which reveals the properties of the bacterial wall so that they can be used to distinguish and classify bacteria The main distinction is between Gram-positive and Gram-negative bacteria

Graph Theory: A branch of mathematics focused on the properties of graphs

graph theory: a branch of mathematics focusing on the properties of a variety of graphs (meaning visual representations of data and their relationships, as opposed to graphs of functions on a Cartesian plane)

Graphing Calculator: A calculator with an advanced screen capable of showing and drawing graphs and other functions

gravimetric analysis - a set of quantitative analytical techniques based on measurement of a sample's mass

Greatest common factor – The largest factor that is common to two or more numbers.

Greatest Common Factor: The largest number common to each set of factors that divides both numbers exactly The greatest common factor of 10 and 20 is 10

green chemistry - branch of chemistry concerned with lessening the environmental effect of chemicals, including development of new materials and processes

ground state - the lowest energy state of an atom, ion, molecule, or subatomic particle

group - a vertical column on the periodic table consisting of elements that share periodic properties

group theory: the mathematical field that studies the algebraic structures and properties of groups and the mappings between them

group: a mathematical structure consisting of a set together with an operation that combines any two of its elements to form a third element, e.g the set of integers and the addition operation form a group

Haber process - method of making ammonia or fixing nitrogen by reacting nitrogen and hydrogen gas

hafnium - transition metal with element symbol Hf and atomic number 72

half-cell - half of an electrolytic or voltaic cell, serving as the site of either oxidation or reduction

half-life (t1/2) - time required to convert half of the reactant to a product or the time required for half of a radioactive isotope to decay into its daughter isotope

halide ion - a singlet halogen atom, which has a charge of -1 (e.g., Cl-)

halogen - an element in Group VIIA of the periodic table (e.g., Br, Cl)

halogenated hydrocarbon - a hydrocarbon that contains one or more halogen atoms

hard water - water that contains high amounts of calcium and/or magnesium cations

hassium - transition metal that is atomic number 108 with element symbol Hs

Healthcare-associated infection: an infection that patients acquire during the course of receiving treatment for other conditions within a hospital or healthcare setting

Healthcare-Associated Infections: a disease contracted in a hospital or other healthcare establishment by a patient who did not have this disease on admission

heat - energy that flows between matter samples because of a temperature difference

heat capacity - quantity of heat needed to raise the temperature of a sample by a specified amount

heat of formation ( ΔHf) - amount of heat absorbed or released during formation of a pure substance from its elements at constant pressure

heat of fusion ( ΔHfus) - the change in enthalpy (heat) for the conversion of one gram or mole of a solid to a liquid at constant temperature and pressure

Heat refers to thermal energy

heavy metal - a dense metal that is toxic at low concentrations

Heisenberg uncertainty principle - principle that states it is impossible to determine both the position and momentum of a particle at once with perfect accuracy

helium - Helium is the name for the element with atomic number 2 and is represented by the symbol He It is a member of the noble gases group

Henderson-Hasselbalch equation - an approximation that relates the pH or pOH of a solution, the pKa or pKb, and the ratio of concentration of dissociated species

Henry's Law - law that states the mass of a gas that will dissolve into solution is directly proportional to the partial pressure of the gas above the solution

Hess's Law - law that states the energy change in an overall reaction equals the sum of the energy changes in its individual (partial) reactions

heterogeneous -- consisting of dissimilar components

heterogeneous mixture - a mixture that lacks a uniform composition such that at least two components are present with identifiable properties

heterogeneous reaction - chemical reaction in which reactants are different phases from each other

Hexagon: A six-sided and six-angled polygon

Hilbert problems: an influential list of 23 open (unsolved) problems in mathematics described by David Hilbert in 1900

Histogram: A graph that uses bars that equal ranges of values

Histology: the study of tissue in order to research tissue composition, structure and renewal and cellular exchanges within themselves

HLA: the acronym of “Human Leukocyte Antigens”: histocompatibility antigens whose role is essential in the tolerance of organ transplants and which are specific to a given individual

holmium - rare earth metal with element symbol Ho and atomic number 67

homogeneous - uniform through its volume

homopolymer - polymer in which every mer unit is identical

hybrid orbital - orbital formed by the combination of two or more atomic orbitals

hydration reaction - reaction in which a hydrogen and hydroxyl ion are attached to a carbon in a C-C double bond

hydrocarbon - molecule consisting entirely of carbon and hydrogen atoms

hydrogen - element with atomic number 1 and symbol H

hydrogen bond - attractive interaction between a hydrogen bonded to an electronegative atom and a different electronegative atom

hydrogenation - reduction reaction that produces hydrogen (usually as H2)

hydrolysis - decomposition reaction in which one reactant is water Reverse of a condensation reaction

hydrometer - instrument used to measure the relative densities of two liquids

hydronium ion - the H3O+cation

hydrophobic - property of repelling water

hydroxyl group - functional group consisting of a hydrogen atom covalently bonded to an oxygen atom (-OH)

hygroscopic - able to absorb or adsorb water from the surroundings

hyperbola: a smooth symmetrical curve with two branches produced by the section of a conical surface

Hyperbola: A type of conic section or symmetrical open curve The hyperbola is the set of all points in a plane, the difference of whose distance from two fixed points in the plane is a positive constant

hyperbolic geometry: a non-Euclidean geometry based on a saddle-shaped plane, in which there are no parallel lines and the angles of a triangle sum to less than 180°

hypertonic - having higher osmotic pressure than another solution

Hypotenuse – In a right triangle it is the side opposite from the 90° angle.

Hypotenuse: The longest side of a right-angled triangle, always opposite to the right angle itself

hypothesis - prediction of an event or proposed explanation of a phenomenon

ideal gas - gas in which molecules have negligible size and kinetic energy dependent only on temperature

ideal gas constant - physical constant in the Ideal Gas Law, equal to the Boltzmann constant but with different units

ideal gas law - PV = nRT where P is pressure, V is volume, n is number of moles, R is the ideal gas constant, and T is temperature

identity: an equality that remains true regardless of the values of any variables that appear within it, e.g for multiplication, the identity is one; for addition, the identity is zero

Identity: An equation that is true for variables of any value

Imaginary number – The square root of a negative number.

imaginary numbers: numbers in the form bi, where b is a real number and i is the “imaginary unit”, equal to √-1 (i.e i2 = -1)

immiscible - property of two substances being unable to combine to form a homogeneous mixture; unable to mix

Immunoassay: diagnostic test based on an antigen/antibody reaction, enabling the detection of infectious agents (bacteria, viruses, parasites) and pathogen markers

Improper fraction – A fraction in which the numerator is larger than the denominator

Improper fraction – A fraction in which the numerator is larger than the denominator.

Improper Fraction: A fraction whose denominator is equal to or greater than the numerator, such as 6/4

In vitro diagnostics: analysis of biological samples (urine, blood, etc.) performed outside the human body

In vivo diagnostics: tests or research performed on a living organism

independent variable - the variable that is controlled or changed in an experiment to test its effect on the dependent variable

indicator - substance that undergoes a visible change when its conditions change (e.g., a pH indicator)

indium - metal with element symbol In and atomic number 49

inductive effect - effect a chemical bond has on the orientation of adjacent bonds in a molecule

inductive reasoning or logic: a type of reasoning that involves moving from a set of specific facts to a general conclusion, indicating some degree of support for the conclusion without actually ensuring its truth

Inequality: A mathematical equation expressing inequality and containing a greater than (>), less than (<), or not equal to (≠) symbol

infinite series: the sum of an infinite sequence of numbers (which are usually produced according to a certain rule, formula or algorithm)

infinitesimal: quantities or objects so small that there is no way to see them or to measure them, so that for all practical purposes they approach zero as a limit (an idea used in the developement of infinitesimal calculus)

infinity: a quantity or set of numbers without bound, limit or end, whether countably infinite like the set of integers, or uncountably infinite like the set of real numbers (represented by the symbol ∞)

inhibitor - substance that slows or prevents a chemical reaction

inorganic chemistry - study of chemistry of molecules of non-biological origin (not containing C-H bonds)

insoluble - unable to dissolve in a solvent

Integer – A whole number. It may be positive, negative, or zero.

Integers: All whole numbers, positive or negative, including zero

integers: whole numbers, both positive (natural numbers) and negative, including zero

integral: the area bounded by a graph or curve of a function and the x axis, between two given values of x (definite integral), found by the operation of integration

integration: the operation in calculus (inverse to the operation of differentiation) of finding the integral of a function or equation

intensive property - property of matter that is independent of the quantity of matter in a sample

Interior angles – Angles formed inside the shape or inside two parallel lines.

intermediate - substance formed in a middle step between reactants and final products

intermolecular force - the sum of all forces between neighboring molecules

internal energy - the total energy (U) of a closed system

Intersecting lines – Lines that come together at a point.

Interval – The numbers that are contained within two specific boundaries.

intrinsic property - property of matter that is independent of the quantity of matter present

inverse proportion - relationship between variable such that their product is a constant value

iodine - Iodine is the name for the element with atomic number 53 and is represented by the symbol I It is a member of the halogen group

ion - atom or molecule which has a different number of protons than electrons and thus a net electrical charge

ionic - pertaining to carrying a net electrical charge at the atomic or molecular level

ionic bond - chemical link between atoms caused by electrostatic force between opposite charged ions

ionic compound - compound formed by ions bonding together due to electrostatic forces (differing electronegativity values)

ionic equation - chemical equation in which electrolytes in aqueous solution are written as dissociated ions

ionic radius - half the distance between two ions just touching each other

ionization energy - energy required to completely remove an electron from a gaseous atom of ion

iridium - Iridium is the name for the element with atomic number 77 and is represented by the symbol Ir It is a member of the transition metals group

iron - Iron is the name for the element with atomic number 26 and is represented by the symbol Fe It is a member of the transition metals group

Irrational number – A number that is not rational (cannot be written as a fraction x/y, with x a natural number and y an integer).

irrational numbers: numbers that can not be represented as decimals (because they would contain an infinite number of non-repeating digits) or as fractions of one integer over another, e.g π, √2, e

Irrational: A number that cannot be represented as a decimal or fraction A number like pi is irrational because it contains an infinite number of digits that keep repeating Many square roots are also irrational numbers

isoelectronic - chemical species that have the same electronic structure and thus same number of valence electrons

isolated system - thermodynamic system that can't exchange energy or matter outside of the system

isomer - chemical species with the same number and type of atoms as another species, but a different arrangement and thus different properties

isomerization process - protocol in which straight chain hydrocarbons are converted into branched chain hydrocarbons

Isosceles triangle – A triangle with two equal sides and two equal angles across from them.

Isosceles: A polygon with two sides of equal length

isotopes - atoms that have the same number of protons, but different numbers of neutrons and thus different atomic weight values

IUPAC - International Union of Pure and Applied Chemistry, an authority on chemical standards

IVD: abbreviation for in vitro diagnostics

joule - SI unit of energy equal to the kinetic energy of a 1 kg mass moving at 1 m/s

Julia set: the set of points for a function of the form z2 + c (where c is a complex parameter), such that a small perturbation can cause drastic changes in the sequence of iterated function values and iterations will either approach zero, approach infinity or get trapped in loop

Kelvin temperature scale - an absolute temperature scale with 100 degrees between the freezing and boiling points of water (although values are given without degrees by convention)

keratin - a fibrous protein produced by chordates It may be found in hair, skin, claws, and wool

ketone - compound containing a carbonyl functional group (C=O) between two groups of atoms

kilo - prefix meaning "one thousand"

Kilometer: A unit of measure equal to 1000 meters

kilopascal (kPa) - unit of pressure exerted by a 10 g mass on a square centimeter There are 1000 Pa in 1 kPa

kinetic energy - energy associated with motion

knot theory: an area of topology that studies mathematical knots (a knot is a closed curve in space formed by interlacing a piece of “string” and joining the ends)

Knot: A closed three-dimensional circle that is embedded and cannot be untangled

krypton - element 36 on the periodic table with symbol Kr

Krypton is a noble gas

labile complex - a complex ion that quickly reaches equilibrium with ligands in the surrounding solution

lanthanides - subset of transition metals characterized by filling of the 4f sublevel, usually atomic number 58-71

lanthanum - element atomic number 57 with element symbol La

lattice energy - enthalpy change of the process by which opposite-charged ions in a gas combine to form a solid ionic lattice

law - a general rule that explains a body of scientific observations Laws are stated in words, but expressed by mathematical equations

Law of Chemical Equilibrium - an expression of the relationship between the concentration of reactants and products of a chemical reaction mixture at equilibrium

Law of Combining Volumes - relation that states the volumes of gases in a chemical reaction are present in the ratio of small integers under conditions where all gases are at the same temperature and pressure

Law of Conservation of Energy - law that states energy can neither be created nor destroyed, although it may change from one form into another

Law of Conservation of Mass - law that states matter in a closed system may be neither created nor destroyed, although it may change forms

Law of Constant Composition - chemistry law that states samples of a pure compound contain the same elements in the same proportions by mass

Law of Definite Proportions - law that states all samples of a compound contain the same proportion of elements by mass

Law of Multiple Proportions - law that states element combine in ratios of small whole numbers to form molecules

lawrencium - actinide with element symbol Lr and atomic number 103

Le Chatelier′s Principle - principle that says that equilibrium of a chemical system will shift in the direction to relieve stress

lead - metal with element symbol Pb and atomic number 82

Least common multiple – The smallest multiple that is common to two or more numbers.

least squares method: a method of regression analysis used in probability theory and statistics to fit a curve-of-best-fit to observed data by minimizing the sum of the squares of the differences between the observed values and the values provided by the model

Lewis acid - chemical species that can act as an electron pair acceptor

Lewis acid base reaction - chemical reaction that forms at least one covalent bond between an electron pair donor (Lewis base) and electron pair acceptor (Lewis acid)

Lewis base - a substance that is an electron pair donor

Lewis structure - representation of a molecule that uses dots to show electrons around atoms and lines to show covalent bonds

ligand - a chemical species that donates or shares at least one electron via a covalent bond with a central ion or atom

Like Fractions: Fractions with the same denominator

Like Terms: Terms with the same variable and same exponents/powers

limit: the point towards which a series or function converges, e.g as x becomes closer and closer to zero, (sin x)⁄x becomes closer and closer to the limit of 1

limiting reactant - the reactant that determines how much product may result from a chemical reaction

Line of Symmetry: A line that divides a figure into two equal shapes

Line Segment: A straight path that has two endpoints, a beginning and an end

Line: A straight infinite path joining an infinite number of points in both directions

line: in geometry, a one-dimensional figure following a continuous straight path joining two or more points, whether infinite in both directions or just a line segment bounded by two distinct end points

Linear equation – An equation where the solution set forms a straight line when it is plotted on a coordinate graph.

linear equation: an algebraic equation in which each term is either a constant or the product of a constant and the first power of a single variable, and whose graph is therefore a straight line, e.g y = 4, y = 5x + 3

Linear Equation: An equation that contains two variables and can be plotted on a graph as a straight line

linear regression: a technique in statistics and probability theory for modelling scattered data by assuming an approximate linear relationship between the dependent and independent variables

lipid - class of fat-soluble molecules, also known as oils and fats

liquefaction - process of converting a material from a solid or gas phase into the liquid phase

liquid - state of matter characterized by having a definite volume but not a definite shape

Listeria: a genus of bacteria that can cause listeriosis, an infectious disease which is potentially serious in new-born babies, pregnant women or individuals with low resistance

lithium - alkali metal with atomic number 3 and element symbol Li

litmus paper - filter paper used as a pH paper that has been treated with a water-soluble dye obtained from lichens

Litmus paper is a specific type of pH paper

logarithm: the inverse operation to exponentiation, the exponent of a power to which a base (usually 10 or e for natural logarithms) must be raised to produce a given number, e.g because 1,000 = 103, the log10 100 = 3

Logarithm: The power to which a base must be raised to produce a given number If nx = a, the logarithm of a, with n as the base, is x Logarithm is the opposite of exponentiation

Logic: Sound reasoning and the formal laws of reasoning

logic: the study of the formal laws of reasoning (mathematical logic the application of the techniques of formal logic to mathematics and mathematical reasoning, and vice versa)

logicism: the theory that mathematics is just an extension of logic, and that therefore some or all mathematics is reducible to logic

London dispersion force - weak intermolecular force between atoms or molecules in close proximity to each other, due to electron repulsion

lone pair - an electron pair in the outer shell of an atom that is not shared or bonded with another atom

Lowest common denominator – The smallest number that can be divided evenly by all denominators in the problem.

lutetium - rare earth metal with element symbol Lu and atomic number 71

macromolecule - molecule containing a very large number of atoms, usually more than 100

Madelung's rule - rule that describes filling of electron orbitals in atoms due to shielding of nuclear charge by inner electrons

magic square: a square array of numbers where each row, column and diagonal added up to the same total, known as the magic sum or constant (a semi-magic square is a square numbers where just the rows and columns, but not both diagonals, sum to a constant)

magnesium - Magnesium is the name for the element with atomic number 12 and is represented by the symbol Mg Magnesium is an alkaline earth metal

main group elements - any of the elements in the s and p blocks of the periodic table

malleable - able to be shaped or pounded with a hammer, usually applied to metals

Mandelbrot set: a set of points in the complex plane, the boundary of which forms a fractal, based on all the possible c points and Julia sets of a function of the form z2 + c (where c is a complex parameter)

manganese - element with atomic number 25 and element symbol Mn

manifold: a topological space or surface which, on a small enough scale, resembles the Euclidean space of a specific dimension (called the dimension of the manifold), e.g a line and a circle are one-dimensional manifolds; a plane and the surface of a sphere are two-dimensional manifolds; etc

manometer - device used to measure gas pressure

Marker: a reagent used to detect the substance to which it is bound A biological marker (biomarker) is a substance that is assayed to help diagnose a pathology

mass - amount of matter a substance contains or property of matter that resists acceleration

mass defect - difference between the mass of an atom and the sum of the masses of its protons, neutrons, and electrons

Mass is a measure of the quantity of matter in a sample

mass number - whole number integer that is the sum of the number of protons and neutrons in the atomic nucleus

mass percentage - concentration calculated as mass of a component divided by total mass of mixture or solution; w/w%

Mass spectrometry: a technique used to identify a molecule and determine its chemical structure by analyzing the mass and the charge of its ions

mass spectroscopy - analytical technique used to separate and/or identify components of a mixture based on mass and electrical charge

matrix: a rectangular array of numbers, which can be added, subtracted and multiplied, and used to represent linear transformations and vectors, solve equations, etc

matter - anything that has mass and occupies volume

Mean – The average of a number of items in a group (total the items and divide by the number of items).

Mean: The mean is the same as the average Add up a series of numbers and divide the sum by the total number of values to find the mean

measurement - quantitative or numerical data describing an object or event

Median – The middle item in an ordered group. If the group has an even number of items, the median is the average of the two middle terms.

Median: The median is the "middle value" in a series of numbers ordered from least to greatest When the total number of values in a list is odd, the median is the middle entry When the total number of values in a list is even, the median is equal to the sum of the two middle numbers divided by two

medicinal chemistry - branch of chemistry concerned with design, synthesis, and study of pharmaceuticals

meitnerium - radioactive transition metal with element symbol Mt and atomic number 109

melting - phase change of matter from solid to liquid

melting point - temperature at which the solid and liquid phase of matter coexist in equilibrium

mendelevium - actinide with atomic number 101 and element symbol Md

meniscus - phase boundary between a liquid in a container and a gas, curved due to surface tension

mercaptan - organic sulfur compound containing an alkyl or aryl group and a thiol group

mercapto group - functional group consisting of a sulfur bonded to a hydrogen; -SH

mercury - transition metal with element symbol Hg and atomic number Hg

Mersenne number: numbers that are one less than 2 to the power of a prime number, e.g 3 (22 – 1); 7 (23 – 1); 31 (25 – 1); 127 (27 – 1); 8,191 (213 – 1); etc

Mersenne primes: prime numbers that are one less than a power of 2, e.g 3 (22 – 1); 7 (23 – 1); 31 (25 – 1); 127 (27 – 1); 8,191 (213 – 1); etc – many, but not all, Mersenne numbers are primes, e.g 2,047 = 211 – 1 = 23 x 89, so 2,047 is a Mersenne number but not a Mersenne prime

metabolism - set of biochemical reactions that store chemical energy and convert it into a form an organism can use

metal - substance that has high conductivity and other metallic properties, including tendency to form cations, often identified by group on the periodic table

metallic character - set of chemical properties associated with metals, including the ability to lose outer valence electrons to form cations

metallic compound - chemical compound that contains one or more metal atoms

metalloid - element with properties intermediate between those of metals and nonmetals (e.g., silicon)

meter - either (a) the base unit of length in the SI system or (b) a device used to measure a quantity

Methicillin: a semi-synthetic penicillin used primarily against non-resistant Staphylococcus aureus

method of exhaustion: a method of finding the area of a shape by inscribing inside it a sequence of polygons whose areas converge to the area of the containing shape (a precursor to the methods of calculus)

methyl - functional group containing a carbon bonded to three hydrogen atoms, -CH3

Microbiology: study of microorganisms In the field of in vitro diagnostics: culturing biological, food and pharmaceutical samples in growth medium allows any bacteria that may be present to multiply.The bacteria are subsequently identified and their susceptibility to antibiotics tested in certain cases

microliter - unit of volume that is one-millionth of a liter one cubic millimeter

micron - unit of length equal to one-millionth of a meter; a micrometer

Microorganism: a living organism of microscopic size

Midpoint: A point that is exactly halfway between two locations

mineral acid - any inorganic acid (e.g., sulfuric acid)

miscible - soluble or able to be mixed to form a solution, typically applied to fluids

Mixed number – A number containing both a whole number and a fraction.

Mixed Numbers: Mixed numbers refer to whole numbers combined with fractions or decimals Example 3 1/2 or 3.5

mixture - combination of two or more substances such that each retains its separate chemical identity (e.g., salt and flour)

Mode: The mode in a list of numbers are the values that occur most frequently

moderator - material that slows or moderates the speed of neutrons

Modular Arithmetic: A system of arithmetic for integers where numbers "wrap around" upon reaching a certain value of the modulus

modular arithmetic: a system of arithmetic for integers, where numbers “wrap around” after they reach a certain value (the modulus), e.g on a 12-hour clock, 15 o’clock is actually 3 o’clock (15 = 3 mod 12)

modulus: a number by which two given numbers can be divided by integer division, and produce the same remainder, e.g 38 ÷ 12 = 3 remainder 2, and 26 ÷ 12 = 2 remainder 2, therefore 38 and 26 are congruent modulo 12, or (38 ≡ 26) mod 12

Mohs scale - Mohs scale is a relative scale rating the hardness of a mineral A mineral with a high Mohs number is able to mark a mineral with a lower Mohs number

moiety - group of atoms in a molecule that are responsible for its characteristic chemical behavior

molality - unit of concentration that is the moles of solute divided by the kilograms of solvent

molar - refers to molarity (moles per liter of solution); e.g a 6 M HCl solution has 6 moles of hydrochloric acid per liter of solution

molar enthalpy of fusion - energy needed to change one mole of a substance from solid to liquid phase at constant pressure and temperature

molar enthalpy of vaporization - energy needed to change one mole of liquid to the gas phase at constant pressure and temperature

molar heat capacity - heat energy required to raise the temperature of 1 mole of a substance 1 Kelvin

molar mass - mass of one mole of a substance

molar volume - volume of one mole of a substance

molarity - unit of concentration that is the number of moles of solute divided by the number of liters of solution

mole - chemical mass unit equal to 6.022 x 1023 molecules, atoms, or other particles

mole fraction - unit of concentration that is the number of moles of a component divided by the total number of moles of a solution

mole ratio - ratio or fraction comparing the numbers of moles of any two components involved in a chemical reaction

Molecular biology: technique that can detect a bacterium, virus, yeast, parasite or a biomarker through the presence of DNA or RNA genetic sequences in a sample

molecular equation - balanced chemical equation in which ionic compounds are expressed as molecules rather than ions

molecular formula - expression of the number and type of atoms in a molecule

molecular geometry - description of the shape of a molecule and the relative positions of its atoms

molecular mass - sum of the atomic masses of atoms in a molecule

molecular orbital - wave function of an electron in a molecule

molecular weight - sum of the atomic weights of atoms in a molecule

molecule - chemical species formed by two or more atoms that share chemical bonds such that they form one unit

molybdenum - transition metal with element symbol Mo and atomic number 42

monatomic ion - an ion formed by a single atom

monomer - a molecule that is a subunit or building block of a polymer

Monomial – An expression in algebra that consists of only one term.

monomial: an algebraic expression consisting of a single term (although that term could be an exponent), e.g y = 7x, y = 2x3

Monomial: An algebraic expression made up of one term

monoprotic acid - acid that donates a single proton or hydrogen atom per molecule in aqueous solution

mother liquor - solution remaining after crystals are removed from a crystallization solution

MRSA: methicillin-resistant Staphylococcus aureus bacterium

MSDS - acronym for Material Safety Data Sheet, a written document outlining safety information about a chemical

multiple bond - a bond formed when two or more pairs of electrons are shared between two atoms

Multiple: The multiple of a number is the product of that number and any other whole number 2, 4, 6, and 8 are multiples of 2

Multiplex: the ability to transmit multiple data on a single physical medium

Multiplicand: A quantity multiplied by another A product is obtained by multiplying two or more multiplicands

Multiplication: Multiplication is the repeated addition of the same number denoted with the symbol x 4 x 3 is equal to 3 + 3 + 3 + 3

Multi-resistant bacteria: bacteria are said to be multi-resistant to antibiotics when they are sensitive only to a small number of the antibiotics customarily used in therapy, as a consequence of the accumulation of natural and acquired resistances

muriatic acid - common name for hydrochloric acid, HCl

Mycobacteria: rod-shaped bacillus-type bacteria Some species of mycobacterium are pathogenic: M leprae responsible for leprosy; M tuberculosis, responsible for tuberculosis

naphthenes - cyclic aliphatic hydrocarbons from petroleum with the general formula CnH2n

natural abundance - average percentage of a given isotope naturally occurring on Earth

Natural number – A counting number.

Natural Numbers: Regular counting numbers

natural numbers: the set of positive integers (regular whole counting numbers), sometimes including zero

Negative number – A number less than zero.

Negative Number: A number less than zero denoted with the symbol - Negative 3 = -3

negative numbers: any integer, ration or real number which is less than 0, e.g -743, -1.4, -√5 (but not √-1, which is an imaginary or complex number)

neodymium - rare earth metal with element symbol Nd and atomic number 60

neon - noble gas with element symbol Ne and atomic number 10

Neon lights contain the noble gas neon

neptunium - actinide with element symbol Np and atomic number 94

net ionic equation - chemical equation that lists only the species participating in the reaction

Net: A two-dimensional shape that can be turned into a two-dimensional object by gluing/taping and folding

network solid - material consisting of an array of repeating covalently bonded atoms

neutral solution - aqueous solution with a pH of 7

neutralization - chemical reaction between an acid and base that results in a neutral solution

neutron - particle in the atomic nucleus that has a mass of 1 and charge of 0

newton (N) - SI unit of force equal to the amount of force needed to accelerate a 1 kg mass 1 m/sec2

nickel - Nickel is the name for the element with atomic number 28 and is represented by the symbol Ni Nickel is a member of the transition metals group

niobium - Niobium is the name for the element with atomic number 41 and is represented by the symbol Nb Niobium is also called Columbium and is a transition metal

nitrogen - Nitrogen is the name for the element with atomic number 7 and is represented by the symbol N Nitrogen is also known as azote and is a member of the nonmetal group

nobelium - actinide with element symbol No and atomic number 102

noble gas - element from Group 8 of the periodic table (e.g., xenon, argon)

noble gas core - shorthand notation used writing atomic electron configuration in which previous noble gas configuration is replaced by the element symbol in brackets

nonbonding electron - electron in an atom that does not participate in a chemical bond with other atoms

non-commutative algebra: an algebra in which a x b does not always equal b x a, such as that used by quaternions

nonelectrolyte - substance that does not dissociate into ions in aqueous solution

non-Euclidean geometry: geometry based on a curved plane, whether elliptic (spherical) or hyperbolic (saddle-shaped), in which there are no parallel lines and the angles of a triangle do not sum to 180°

Nonlinear equation – An equation where the solution set does not form a straight line when it is plotted on a coordinate graph

Nonlinear equation – An equation where the solution set does not form a straight line when it is plotted on a coordinate graph.

nonmetal - element that does not display metallic properties, typically referring to elements located in the upper right corner of the periodic table

nonoxidizing acid - an acid that cannot act as an oxidizing agent

nonpolar bond - chemical bond with even distribution of charge such that it does not have positive or negative poles

nonpolar molecule - molecule that has even distribution of charge such that it does not have positive and negative sides

nonspontaneous reaction - chemical reaction that cannot occur without input of external work

nonvolatile - substance that does not readily evaporate into a gas under ordinary conditions

Norm: The mean or average; an established pattern or form

normal (Gaussian) distribution: a continuous probability distribution in probability theory and statistics that describes data which clusters around the mean in a curved “bell curve”, highest in the middle and quickly tapering off to each side

normal boiling point - temperature at which a liquid boils at 1 atm of pressure (sea level)

normal concentration - either refers to normal concentration in which the concentration of solutes is the same in two samples or refers to gram equivalent weight of a solute in solution (N)

Normal Distribution: Also known as Gaussian distribution, normal distribution refers to a probability distribution that is reflected across the mean or center of a bell curve

normal melting point - temperature at which a solid melts at 1 atm of pressure

normality (N) - measure of concentration equal to gram equivalent weight per liter of solution

Nth Root: The nth root of a number is how many times a number needs to be multiplied by itself to achieve the value specified Example: the 4th root of 3 is 81 because 3 x 3 x 3 x 3 = 81

nuclear fission - splitting of atomic nuclei into two or more lighter nuclei, accompanied by an energy release

nuclear radiation - particles and photons emitted during reactions in the atomic nucleus

nucleation - process of vapor droplets condensing into a liquid, bubbles forming in a boiling liquid, or particle accretion to grow crystals

Nucleic acid: a naturally-occurring molecule found in each cell It has the ability to hold and transmit coded hereditary instructions allowing for an organism's development There are two types of nucleic acids: DNA and RNA

nucleophile - atom or molecule that donates an electron pair to form a covalent bond

nucleotide - organic molecule comprised of a nucleotide base, ribose or deoxyribose, and one or more phosphate groups

nucleus - positively charged center of an atom, made from protons and neutrons

nuclide - an atom or ion characterized by the proton and neutron composition of its nucleus

null hypothesis - proposition that there is no effect of a treatment or no relationship between an independent and dependent variable

Number line – A visual representation of the positive and negative numbers and zero

Number line – A visual representation of the positive and negative numbers and zero.

number line: a line on which all points correspond to real numbers (a simple number line may only mark integers, but in theory all real numbers to +/- infinity can be shown on a number line)

Number Line: A line whose points correspond to numbers

number theory: the branch of pure mathematics concerned with the properties of numbers in general, and integers in particular

Numeral: A written symbol denoting a number value

Numerator – The top symbol or number of a fraction.

Numerator: The top number in a fraction The numerator is divided into equal parts by the denominator

nutraceutical - a food or part of food that confers health or medical benefits

Obtuse angle – An angle which is larger than 90° but less than 180°.

Obtuse Angle: An angle measuring between 90° and 180°

Obtuse triangle – A triangle which contains an obtuse angle.

Obtuse Triangle: A triangle with at least one obtuse angle

Octagon: A polygon with eight sides

octane number - value that indicates resistance of motor fuel to engine knock relative to the knock from isooctane (100) and heptane (0)

octet - group of 8 valence electrons around an atom

octet rule - principal that atoms in an atomic bond share their 8 outer electrons

Odd number – An integer (whole number) that is not divisible evenly by 2.

Odd Number: A whole number that is not divisible by 2

Odds: The ratio/likelihood of a probability event happening The odds of flipping a coin and having it land on heads are one in two

Oncology (or cancerology): the medical specialty of the study, diagnosis and treatment of cancers

open system - a system able to freely exchange matter and energy with its surroundings

Operation: Refers to addition, subtraction, multiplication, or division

orbital - mathematical function that describes the wavelike behavior of an electron

Order of Operations: A set of rules used to solve mathematical problems in the correct order This is often remembered with acronyms BEDMAS and PEMDAS

Ordered pair – Any pair of elements (x,y) where the first element is x and the second element is y. These are used to identify or plot points on coordinate graphs.

ordinal numbers: an extension of the natural numbers (different from integers and from cardinal numbers) used to describe the order type of sets i.e the order of elements within a set or series

Ordinal: Ordinal numbers give relative position in a set: first, second, third, etc

organic chemistry - study of the chemistry of compounds containing carbon chemical bonded to hydrogen

Origin – The intersection point of the two number lines of a coordinate graph. The intersection point is represented by the coordinates (0,0).

osmium - Osmium is the name for the element with atomic number 76 and is represented by the symbol Os It is a member of the transition metal group

osmosis - movement of solvent molecules across a semipermeable membrane from a dilute solution to a more concentrated solution, thus diluting it and equalizing concentration on both sides of the membrane

Outcome: Used in probability to refer to the result of an event

oxidant - a reactant that oxidizes or removes electrons from another reactant in a redox reaction

oxidation - loss of electrons by an atom, molecule or ion in a chemical reaction

oxidation number - the electrical charge of a central atom in a coordination compound if all electron pairs and ligands were removed

oxidation state - the difference between the number of electrons in an atom in a compound compared with the number of electrons in a neutral atom of the element

oxide - an ion of oxygen with an oxidation state equal to 2- (e.g., iron oxide)

oxidizer - a reactant that removes electrons from another reactant in a redox reaction

oxidizing agent - an oxidizer; a reactant that removes electrons from another reactant

oxyanion - an anion that contains the element oxygen

oxygen - Oxygen is the name for the element with atomic number 8 and is represented by the symbol O It is a member of the nonmetal group

palladium - transition metal with element symbol Pd and atomic number 46

parabola: a type of conic section curve, any point of which is equally distant from a fixed focus point and a fixed straight line

Parabola: An open curve whose points are equidistant from a fixed point called the focus and a fixed straight line called the directrix

paradox: a statement that appears to contradict itself, suggesting a solution which is actually impossible

Parallel lines – Two or more lines which are always the same distance apart. They never meet.

Parallelogram: A quadrilateral with two sets of opposite sides that are parallel

paramagnetism - property of material characterized by being attracted to a magnetic field

Parasite: an organism that feeds off, lives or reproduces itself by establishing a lasting interaction with another organism (the host)

parent atom - atom that undergoes radioactive decay, resulting in one or more daughter atoms

parent nuclide - nuclide that decays into a specific daughter nuclide during radioactive decay

partial differential equation: a relation involving an unknown function with several independent variables and its partial derivatives with respect to those variables

partial pressure - the pressure a gas in a mixture of gases would exert if it occupied the volume by itself, at the same temperature

particulate - small distinct solids suspended in a gas or liquid

parts per million (PPM) - unit of concentration that is one part solute per one million parts solvent

Pascal (Pa) - SI unit of pressure equal to the force of 1 Newton per square meter

Pascal’s Triangle: a geometrical arrangement of the coefficients of the polynomial expansion of a binomial power of the form (x + y)n as a symmetrical triangle of numbers

Pathogen: a microbe that causes or has the potential to cause an infectious disease

Pauli exclusion principle - principle that says no two electrons or other fermions can have identical quantum numbers in the same atom or molecule

PCR (Polymerase Chain Reaction): molecular biology technology for in vitro amplification of genetic sequences, used to copy known DNA or RNA sequences in large quantities (by an order of magnitude of a billion) from an initially small quantity This technology is particularly useful for detecting the presence of viruses

PCT (Procalcitonin): an early and specific host marker of a bacterial infection, PCT is useful to adapt antimicrobial prescriptions

Pentagon: A five-sided polygon Regular pentagons have five equal sides and five equal angles

percent composition - percent by mass of each element in a compound

percent yield - percent ratio of actual yield divided by theoretical yield

Percent: A ratio or fraction with the denominator 100

Percentage – A common fraction with 100 as its denominator.

perfect number: a number that is the sum of its divisors (excluding the number itself), e.g 28 = 1 + 2 + 4 + 7 + 14

Perimeter: The total distance around the outside of a polygon This distance is obtained by adding together the units of measure from each side

period - horizontal row of the periodic table; elements with the same highest unexcited electron energy level

periodic function: a function that repeats its values in regular intervals or periods, such as the trigonometric functions of sine, cosine, tangent, etc

periodic law - law that states the properties of elements recur in a predictable and systematic way when they are arranged by increasing atomic number

periodic table - tabular arrangement of elements by increasing atomic number, ordered according to trends in recurring properties

periodic trend - regular variation in the properties of elements with increasing atomic number

periodicity - recurring variations in element properties with increasing atomic number due to trends in atomic structure

periplanar - describes two atoms or groups of atoms in the same plane as each other with respect to a single bond

permutation: a particular ordering of a set of objects, e.g given the set {1, 2, 3}, there are six permutations: {1, 2, 3}, {1, 3, 2}, {2, 1, 3}, {2, 3, 1}, {3, 1, 2}, and {3, 2, 1}

peroxide - a polyatomic anion with molecular formula O22-

Perpendicular lines – Two lines which intersect at right angles.

Perpendicular: Two lines or line segments intersecting to form a right angle

petroleum - crude oil; natural flammable hydrocarbon mixture found in geologic formations

pH - measure of the hydrogen ion concentration, reflecting how acidic or basic a substance is

pH indicator - compound that changes color over a range of pH values

pH meter - instrument that measure pH of a solution based on the voltage between two electrodes in the solution

Phage recombinant protein: bacteriophage tail protein that has been obtained by a biological process Bacteriophages: highly specific viruses that only infect bacteria They are used for the targeted capture of bacteria and to isolate them

phase - distinct form of matter with uniform chemical and physical properties

phase change - change in the state of matter of a sample (e.g., liquid to vapor)

phase diagram - chart showing the phase of a substance according to temperature and pressure

phenolphthalein - an organic pH indicator, C20H14O4

phlogiston - Phlogiston was believed to be a substance all combustible matter contained and released when burned Phlogiston theory was an early chemical theory to explain the process of oxidation Phlogiston had no odor, taste, color or mass Deflogisticated substances were called the calx of the substance

phosphorescence - luminescence produced when electromagnetic energy (usually UV light) kicks an electron from a lower to higher energy state A photon is released when the electron falls to a lower state

phosphorus - nonmetal with element symbol P and atomic number 15

photon - discrete packet of electromagnetic radiation

physical change - change that alters the form of matter but not its chemical composition

physical property - characteristic of matter that may be observed and measured without changing the identity of the sample

Pi (π) – A constant that is used for determining the circumference or area of a circle. It is equal to approximately 3.14.

pi (π): the ratio of a circumference of a circle to its diameter, an irrational (and transcendental) number approximately equal to 3.141593…

pi bond - covalent bond formed between two neighbor atom unbonded pi orbitals

Pi: Pi is used to represent the ratio of a circumference of a circle to its diameter, denoted with the Greek symbol π

pKa - negative base 10 log of the acid dissociation constant; lower pKa correlates to stronger acid

pKb - negative base 10 log of the base dissociation constant; lower pKa correlates with stronger base

place value: positional notation for numbers, allowing the use of the same symbols for different orders of magnitude, e.g the “one’s place”, “ten’s place”, “hundred’s place”, etc

Planck's constant - proportionality constant that relates photon energy to frequency; 6.626 x 10-34 J·sec

plane: a flat two-dimensional surface (physical or theoretical) with infinite width and length, zero thickness and zero curvature

Plane: When a set of points join together to form a flat surface that extends in all directions, this is called a plane

plasma - state of matter with no defined shape or volume consisting of ions and electrons

platinum - transition metal with atomic number 78 and element symbol Pt

Platonic solids: the five regular convex polyhedra (symmetrical 3-dimensional shapes): the tetrahedron (made up of 4 regular triangles), the octahedron (made up of 8 triangles), the icosahedron (made up of 20 triangles), the cube (made up of 6 squares) and the dodecahedron (made up of 12 pentagons)

plutonium - Plutonium is the name for the element with atomic number 94 and is represented by the symbol Pu It is a member of the actinide group

pnictogen - member of the nitrogen element group

POC (point-of-care) - POCT (point-of-care testing): services offered “at the bedside”, including in particular the analysis of the diagnosis

pOH - measure of the hydroxide ion concentration in an aqueous solution

polar bond - type of covalent bond in which the electrons are unequally shared between the atoms

polar coordinates: a two-dimensional coordinate system in which each point on a plane is determined by its distance r from a fixed point (e.g the origin) and its angle θ (theta) from a fixed direction (e.g the x axis)

polar molecule - molecule containing polar bonds such that the sum of the bond dipole moments is not zero

polonium - element atomic number 84 with element symbol Po

polyatomic ion - ion comprised of two or more atoms

Polygon: Line segments joined together to form a closed figure Rectangles, squares, and pentagons are just a few examples of polygons

polymer - large molecule made of rings or chains of repeated monomer subunits

Polynomial – An expression in algebra that consists of two or more terms

Polynomial – An expression in algebra that consists of two or more terms.

polynomial: an algebraic expression or equation with more than one term, constructed from variables and constants using only the operations of addition, subtraction, multiplication and non-negative whole-number exponents, e.g 5x2 – 4x + 4y + 7

Polynomial: The sum of two or more monomials

polynuclear aromatic hydrocarbon - hydrocarbon made of fused aromatic rings

polyprotic acid - acid able to donate more than one hydrogen atom or proton per molecule in an aqueous solution

Positive number – A number greater than zero

positron - the antimatter counterpart to an electron, which has a charge of +1

potassium - alkali metal with element symbol K and atomic number 19

potential difference - work required to move an electric charge from one point to another

potential energy - energy due to an object's position

Power – A product of equal factors. 3 x 3 x 3 = 33, read as “three to the third power” or “the third power of three.” Power and exponent can be used interchangeably.

PPB - parts per billion

PPM - parts per million

praseodymium - rare earth element with symbol Pr and atomic number 59

precipitate - to form an insoluble compound by reacting salts or altering a compound's solubility

precipitation reaction - chemical reaction between two soluble salts in which one product is an insoluble salt

pressure - measure of force per unit area

primary standard - very pure reagent

Prime number – A number th at can be divided by only itself and one.

prime numbers: integers greater than 1 which are only divisible by themselves and 1

Prime Numbers: Prime numbers are integers greater than 1 that are only divisible by themselves and 1

principal energy level - primary energy signature of an electron, indicated by quantum number n

principal quantum number - quantum number n that describes the size of an electron orbital

probability theory: the branch of mathematics concerned with analysis of random variables and events, and with the interpretation of probabilities (the likelihood of an event happening)

Probability: The likelihood of an event happening

product - substance formed as a result of a chemical reaction

Product: The sum obtained through multiplication of two or more numbers

projective geometry: a kind of non-Euclidean geometry which considers what happens to shapes when they are projected on to a non-parallel plane, e.g a circle may be projected into an ellipse or a hyperbola

promethium - rare earth element with atomic number 61 and element symbol Pm

proof - volume percentage of ethyl alcohol in an alcoholic beverage

Proper fraction – A fraction in which the numerator is less than the denominator.

Proper Fraction: A fraction whose denominator is greater than its numerator

property - characteristic of matter fixed by its state

Proportion – Written as two equal ratios. For example, 5 is to 4 as 10 is to 8, or 5/4 = 10/8.

protactinium - actinide with atomic number 91 and element symbol Pa

Protein: a basic constituent of all living cells A biological macromolecule is composed of one or more amino acid chains linked by peptide bonds

proton - component of the atomic nucleus with a defined mass of 1 and charge of +1

protonation - addition of a proton to an atom, ion, or molecule

Protractor: A semi-circle device used for measuring angles The edge of a protractor is subdivided into degrees

PSI - unit of pressure; pounds per square inch

Pulmonary embolism: obstruction of one of the branches of the pulmonary artery or of the pulmonary artery itself by a blood clot

pure substance - sample of matter with constant composition and distinct chemical properties

Pythagoras’ (Pythagorean) theorem: the square of the hypotenuse of a right angled triangle is equal to the sum of the squares of the two sides (a2 + b2 = c2)

Pythagorean theorem – A theorem concerning right triangles. It states that the sum of the squares of a right triangle’s two legs is equal to the square of the hypotenuse (a2 + b2 = c2).

Pythagorean triples: groups of three positive integers a, b and c such that the a2 + b2 = c2 equation of Pythagoras’ theorem, e.g ( 3, 4, 5), ( 5, 12, 13), ( 7, 24, 25), ( 8, 15, 17), etc

Quadrant: One quarter (qua) of the plane on the Cartesian coordinate system The plane is divided into 4 sections, each called a quadrant

Quadrants – The four divisions on a coordinate graph.

Quadratic equation – An equation that may be expressed as Ax2 + Bx + C = 0.

quadratic equation: a polynomial equation with a degree of 2 (i.e the highest power is 2), of the form ax2 + bx + c = 0, which can be solved by various methods including factoring, completing the square, graphing, Newton’s method and the quadratic formula

Quadratic Equation: An equation that can be written with one side equal to 0 Quadratic equations ask you to find the quadratic polynomial that is equal to zero

quadrature: the act of squaring, or finding a square equal in area to a given figure, or finding the area of a geometrical figure or the area under a curve (such as by a process of numerical integration)

Quadrilateral: A four-sided polygon

Quadruple: To multiply or to be multiplied by 4

qualitative analysis - determination of the chemical composition of a sample

Qualitative analysis determines the composition of a sample

Qualitative: Properties that must be described using qualities rather than numbers

Quality indicator: term used in food processing to define the microorganisms responsible for visual or taste alterations (e.g., mold or bacterial contamination) Quality indicator counts are used to assess product hygiene

quantitative analysis - determination of the amount or quantity of components in a sample

quantum - a discrete packet of matter or energy, plural is quanta

quantum number - value used to describe the energy levels of atoms or molecules There are four quantum numbers

quartic equation: a polynomial having a degree of 4 (i.e the highest power is 4), of the form ax4 + bx3 + cx2 + dx + e = 0, the highest order polynomial equation that can be solved by factorization into radicals by a general formula

Quartic: A polynomial having a degree of 4

quaternions: a number system that extends complex numbers to four dimensions (so that an object is described by a real number and three complex numbers, all mutually perpendicular to each other), which can be used to represent a three-dimensional rotation by just an angle and a vector

quintic equation: a polynomial having a degree of 5 (i.e the highest power is 5), of the form ax5 + bx4 + cx3 + dx2 + ex + f = 0, not solvable by factorization into radicals for all rational numbers

Quintic: A polynomial having a degree of 5

Quotient: The solution to a division problem

radiation - emitted energy in the form of rays, waves, or particles

Radiation refers to any form of emitted energy

Radical sign – A symbol that designates a square root.

radioactive tracer - radioactive element or compound added to a material to monitor its progress through a system

radioactivity - spontaneous emission of radiation as particles or photons from a nuclear reaction

radium - Radium is the name for the element with atomic number 88 and is represented by the symbol Ra It is a member of the alkaline earth metals group

Radius – A line segment where the endpoints lie one at the center of a circle and one on the circle. The term also refers to the length of this segment.

Radius: A distance found by measuring a line segment extending from the center of a circle to any point on the circle; the line extending from the center of a sphere to any point on the outside edge of the sphere

radon - radioactive gas with element symbol Rn and atomic number 86

Range: The difference between the maximum and minimum in a set of data

Raoult's Law - relation that states the vapor pressure of a solution depends on the mole fraction of solute added to the solution

Ratio – A comparison between two numbers or symbols May be written x:y, x/y, or x is to y

Ratio – A comparison between two numbers or symbols. May be written x:y, x/y, or x is to y.

Ratio: The relationship between two quantities Ratios can be expressed in words, fractions, decimals, or percentages Example: the ratio given when a team wins 4 out of 6 games is 4/6, 4:6, four out of six, or ~67%

Rational number – An integer or fraction such as 7/7 or 9/4 or 5/1. Any number that can be written as a fraction x/y with x a natural number and y an integer.

rational numbers: numbers that can be expressed as a fraction (or ratio) a⁄b of two integers (the integers are therefore a subset of the rationals), or alternatively a decimal which terminates after a finite number of digits or begins to repeat a sequence

Ray: A straight line with only one endpoint that extends infinitely

reactant - starting material for a chemical reaction

reaction - a chemical change that forms new substances

reaction quotient - Q - ratio of the concentration of products of a reaction to the concentration of the reactants

reaction rate - the speed at which chemical reactants form products

reagent - compound or mixture added to a system to produce a reaction or test if one occurs

real gas - gas that does not behave as an ideal gas because its molecules interact with one another

real numbers: all numbers (including natural numbers, integers, decimals, rational numbers and irrational numbers) which do not involve imaginary numbers (multiples of the imaginary unit i, or the square root of -1), may be thought of as all points on an infinitely long number line

Reciprocal – The multiplicative inverse of a number. For example, 2/3 is the reciprocal of 3/2.

reciprocal: a number which, when multiplied by x yields the multiplicative identity 1, and can therefore be thought of as the inverse of multiplication, e.g the reciprocal of x is 1⁄x, the reciprocal of 3⁄5 is 5⁄3

Rectangle: A parallelogram with four right angles

redox indicator - compound that changes color at a specific potential difference

redox reaction - set of chemical reactions involving reduction and oxidation

redox titration - titration of reducing agent by an oxidizing agent or vice versa

Reducing – Changing a fraction into its lowest terms. For example, 3/6 is reduced to ½.

reduction - half reaction in which a chemical species decreases its oxidation number, generally by gaining electrons

Reflection: The mirror image of a shape or object, obtained from flipping the shape on an axis

refrigerant - compound that readily absorbs heat and releases it at a higher temperature and pressure

relative density - ratio of density of a substance to the density of water

relative error - uncertainty of a measurement compared to the size of the measurement

relative standard deviation - measure of precision of data, calculated by dividing standard deviation by the average of data values

relative uncertainty - relative error; uncertainty of a measurement compared to the size of the measurement

Remainder: The number left over when a quantity cannot be divided evenly A remainder can be expressed as an integer, fraction, or decimal

Repeating Decimal: A decimal with endlessly repeating digits Example: 88 divided by 33 equals 2.6666666666666...("2.6 repeating")

residue - matter remaining after evaporation or distillation or an undesirable reaction byproduct or a recognizable portion of a larger molecule

resonance - average of two or more Lewis structure, differing in the position of electrons

reverse osmosis - filtration method that works by applying pressure on one side of a semipermeable membrane

reversible reactions - chemical reaction in which the products act as reactants for the reverse reaction

rhenium - transition metal with atomic number 75 and element symbol Re

Rheumatoid arthritis: the most frequent chronic inflammatory rheumatism Its cause is not fully known, but it is one of the autoimmune diseases (the body produces antibodies against its own tissues)

rhodium - transition metal with atomic number 45 and element symbol Rh

Rhombus: A parallelogram with four sides of equal length and no right angles

Riemannian geometry: a non-Euclidean geometry that studies curved surfaces and differentiable manifolds in higher dimensional spaces

Right angle – An angle which measures 90°.

Right Angle: An angle equal to 90°

Right triangle – A triangle which contains a 90° angle.

right triangle: a triangle (three sided polygon) containing an angle of 90°

Right Triangle: A triangle with one right angle

RNA - ribonucleic acid, a molecule which codes for amino acid sequences

RNA: the acronym of "ribonucleic acid" A polymer similar to DNA which, like DNA, has a role as a vector of genetic information The sugar in RNA is a ribose

roasting - metallurgical process in which a sulfide ore is heated in air to form a free metal or metal oxide

roentgenium - radioactive element with atomic number 111 and element symbol Rg

room temperature - temperature that is comfortable for humans, typically around 300 K

RT - abbreviation for room temperature; ambient temperature that is comfortable for humans

rubidium - Rubidium is the name for the element with atomic number 37 and is represented by the symbol Rb It is a member of the alkali metal group

ruthenium - transition metal with atomic number 45 and element symbol Ru

rutherfordium - radioactive transition metal with element symbol Rf and atomic number 104

salt bridge - connection containing a weak electrolyte located between the oxidation and reduction half cells of a galvanic cell

samarium - rare earth element with atomic number 62 and element symbol Sm

saponification - reaction between triglycerides and either sodium hydroxide or potassium hydroxide to form a fatty acid salt called soap and glycerol

saturated - either a substance in which all atoms are linked by single bonds, a solution that contains maximum dissolved solute concentration, or a thoroughly wetted material

saturated fat - lipid containing only single C-C bonds

saturated solution - chemical solution containing the maximum concentration of dissolved solute for that temperature

Scalene triangle – A triangle in which none of the sides or angles are equal.

Scalene Triangle: A triangle with three unequal sides

scandium - Scandium is the name for the element with atomic number 21 and is represented by the symbol Sc It is a member of the transition metals group

science - the systematic study of the nature and behavior of the world using observation and experimentation

scientific law - general rule that explains a body of observations in the form of a mathematical or verbal statement and implies a cause an effect relationship between observations

scientific method - system of acquiring knowledge and solving problems through observation and experimental testing of hypotheses

Scientific notation – A number between 1 and 10 and multiplied by a power of 10. Used for writing very large or very small numbers.

seaborgium - radioactive transition metal with element symbol Sg and atomic number 106

second quantum number - ℓ, the quantum number associated with the angular momentum of an atomic electron

Sector: The area between an arc and two radii of a circle, sometimes referred to as a wedge

selenium - nonmetal with element symbol Se and atomic number 34

self-similarity: object is exactly or approximately similar to a part of itself (in fractals, the shapes of lines at different iterations look like smaller versions of earlier shapes)

semi-metal - element with a partially filled p orbital, causing it to exhibit properties intermediate between those of metals and nonmetals

Sepsis: a serious systemic infection characterized by the presence of bacteria, fungi, viruses and parasites in the blood and combined with an inflammatory immune-reaction (host response) that can result in the rapid deterioration of the patient’s general condition leading to possible organ failure

Septicaemia: serious systemic infection of the organism by pathogenic germs, indicated by the presence of microorganisms in the blood

sequence: an ordered set whose elements are usually determined based on some function of the counting numbers, e.g a geometric sequence is a set where each element is a multiple of the previous element; an arithmetic sequence is a set where each element is the previous element plus or minus a number

Set – A group of objects, numbers, etc.

set: a collection of distinct objects or numbers, without regard to their order, considered as an object in its own right

SI - System Internationale, the standard metric system of units

sigma bond - covalent bonds formed by overlapping of outer orbitals of adjacent atoms

significant digits: the number of digits to consider when using measuring numbers, those digits that carry meaning contributing to its precision (i.e ignoring leading and trailing zeros)

simplest formula - ratio of elements in a compound

Simplify – To combine terms into fewer terms.

simultaneous equations: a set or system of equations containing multiple variables which has a solution that simultaneously satisfies all of the equations (e.g the set of simultaneous linear equations 2x + y = 8 and x + y = 6, has a solution x = 2 and y = 4)

single displacement reaction - chemical reaction in which an ion of one reactant is exchanged for the corresponding ion of another reactant

skeletal structure - two-dimensional graphic representation of atoms and bonds in a molecule using element symbols and solid lines for bonds

Slope: Slope shows the steepness or incline of a line and is determined by comparing the positions of two points on the line (usually on a graph)

slope: the steepness or incline of a line, determined by reference to two points on the line, e.g the slope of the line y = mx + b is m, and represents the rate at which y is changing per unit of change in x

sodium - Sodium is the name for the element with atomic number 11 and is represented by the symbol Na

sol - type of colloid in which solid particles are suspended in a liquid

solid - state of matter characterized by high degree of organization, with a stable shape and volume

solidification - phase change that results in formation of a solid

solubility - maximum amount of solute that may be dissolved in a specified solute

solubility product - Ksp, the equilibrium constant for a chemical reaction in which a solid ionic compound dissolves to yield its ions in solution

solute - substance that is dissolved in a chemical solution

solution - homogeneous mixture of two or more substances

Solution, or Solution set – The entirety of answers that may satisfy the equation.

solvent - component of a solution present in the greatest proportion

specific gravity - ratio of the density of a substance to the density of water

specific heat - quantity of heat required to raise the temperature of a mass a specified amount

specific heat capacity - amount of heat needed to raise the temperature of a substance per unit mass

spectator ion - ion found in the same amount on both the reactant and product sides of a chemical reaction that does not affect equilibrium

spectroscopy - analysis of the interaction between matter and any portion of the electromagnetic spectrum

spectrum - characteristic wavelengths of electromagnetic radiation emitted or absorbed by an object or substance

spherical geometry: a type of non-Euclidean (elliptic) geometry using the two-dimensional surface of a sphere, where a curved geodesic (not a straight line) is the shortest paths between points

spherical trigonometry: a branch of spherical geometry which deals with polygons (especially triangles) on the sphere, and the relationships between their sides and angles

spin quantum number (Ms) - fourth quantum number, which indicated orientation of intrinsic angular momentum of an electron in an atom

spontaneous fission - spontaneous splitting of an atomic nucleus into two smaller nuclei and usually neutrons, accompanied by the release of energy

spontaneous process - process which can occur without any energy input from the surroundings

Square – The resulting number when a number is multiplied by itself. Also, a four-sided figure with equal sides and four right angles. The opposite sides are parallel.

Square root – The number which when multiplied by itself gives you the original number. For example, 6 is the square root of 36.

Square Root: A number squared is multiplied by itself; the square root of a number is whatever integer gives the original number when multiplied by itself For instance, 12 x 12 or 12 squared is 144, so the square root of 144 is 12

standard - reference used to calibrate measurements

standard hydrogen electrode - SHE, the standard measurement of electrode potential for the thermodynamic scale of redox potentials

standard oxidation potential - potential in volts generated by an oxidation half-reaction compared to the standard hydrogen electrode at 25 °C, 1 atm pressure and a concentration of 1 M

standard solution - a solution with a precisely known concentration

standard temperature and pressure - STP, 273 K (0° Celsius or 32° Fahrenheit) and 1 atm pressure

Staphylococcus: a genus of Gram-positive bacteria, usually observed in clusters resembling bunches of grapes

state of matter - homogeneous phase of matter (e.g., solid, liquid)

steam distillation - distillation process in which steam or water is added to lower boiling points of compounds

steel - an alloy of iron that contains carbon

Stem and Leaf: A graphic organizer used to organize and compare data Similar to a histogram, stem and leaf graphs organize intervals or groups of data

steric number - number of atoms bonded to a central atom of an molecule plus number of lone electron pairs attached to the central atom

stock solution - concentrated solution intended to be diluted to a lower concentration for actual use

stoichiometry - study of quantitative relationships between substances undergoing a physical or chemical change

STP - standard temperature and pressure; 273 K (0° Celsius or 32° Fahrenheit) and 1 atm pressure

Straight angle – An angle which is equal to 180°.

Straight line – The shortest distance between two points. It continues indefinitely in both directions.

strong acid - acid that completely dissociates into its ions in aqueous solution

strong base - base that completely dissociates into its ions in aqueous solution (e.g., NaOH)

strong electrolyte - electrolyte that completely dissociates in aqueous solution

strontium - alkaline earth with element symbol Sr and atomic number 38

sublimation - phase transition from solid phase directly to vapor phase

subset: a subsidiary collection of objects that all belong to, or is contained in, an original given set, e.g subsets of {a, b} could include: {a}, {b}, {a, b} and {}

subshell - subdivision of electron shells separated by electron orbitals (e.g., s, p, d, f)

substituent - atom or functional group that replaces a hydrogen atom in a hydrocarbon

substitution reaction - chemical reaction in which a functional group or atom is replaced by another functional group or atom

substrate - medium on which a reaction occurs or reagent that offers a surface for absorption

Substrate: a molecule used as a starting product which binds to the active ste of ain enzyme and is converted into one or more products

Subtraction: The operation of finding the difference between two numbers or quantities by "taking away" one from the other

sulfur - Sulfur is the name for the element with atomic number 16 and is represented by the symbol S

supernate - the liquid result of a precipitation reaction

supersaturated - supercooled; condition in which a liquid has been cooled to a temperature below which crystallization normally occurs, yet without solid formation

Supplementary angles – Two angles that when combined the sum equals 180°.

Supplementary Angles: Two angles are supplementary if their sum is equal to 180°

surd: the n-th root a number, such as √5, the cube root of 7, etc

surface tension - physical property equal to the force per unit area needed to expand the surface of a liquid

surfactant - species that acts as a wetting agent to lower liquid surface tension and increase spreadability

suspension - heterogeneous mixture of solid particles in a fluid

symmetry: the correspondence in size, form or arrangement of parts on a plane or line (line symmetry is where each point on one side of a line has a corresponding point on the opposite side, e.g a picture a butterfly with wings that are identical on either side; plane symmetry refers to similar figures being repeated at different but regular locations on the plane)

Symmetry: Two halves that match perfectly and are identical across an axis

symmetry: the correspondence in size, form or arrangement of parts on a plane or line (line symmetry is where each point on one side of a line has a corresponding point on the opposite side, e.g. a picture a butterfly with wings that are identical on either side; plane symmetry refers to similar figures being repeated at different but regular locations on the plane)

Syndromic approach: medical approach based on analyzing a syndrome (i.e., a set of symptoms and/or clinical signs) that uses a single test to identify the disease-causing organism(s) responsible for this syndrome, whether they are viruses, bacteria, fungi or parasites

synthesis reaction - direct combination reaction; chemical reaction in which two or more species combine to form a more complex product

Tangent: A straight line touching a curve from only one point

tantalum - transition metal with element symbol Ta and atomic number 73

technetium - transition metal with element symbol Tc and atomic number 43

tellurium - metalloid with element symbol Te and atomic number 52

temperature - property of matter that is a measure of the kinetic energy of its particles; measure of heat or cold

tensor: a collection of numbers at every point in space which describe how much the space is curved, e.g. in four spatial dimensions, a collection of ten numbers is needed at each point to describe the properties of the mathematical space or manifold, no matter how distorted it may be

terbium - rare earth element with symbol Tb and atomic number 65

Term – A literal or numerical expression that has its own sign.

term: in an algebraic expression or equation, either a single number or variable, or the product of several numbers and variables separated from another term by a + or – sign, e.g in the expression 3 + 4x + 5yzw, the 3, the 4x and the 5yzw are all separate terms

Term: Piece of an algebraic equation; a number in a sequence or series; a product of real numbers and/or variables

Tessellation: Congruent plane figures/shapes that cover a plane completely without overlapping

Test tubes are a common type of chemistry glassware

tetrahedral - molecular geometry in which a central atom form four bonds directed toward the corners of a regular tetrahedron

Texas carbon - a carbon atom that forms five covalent bonds, forming a structure resembling a star

thallium - metal with atomic number 81 and element symbol Tl

The Celsius scale is a common temperature scale in chemistry

The flame test is an analytical technique used to help identify metal ions

The Joule is a unit of energy

The periodic table organizes elements according to trends in their properties

theorem: a mathematical statement or hypothesis which has been proved on the basis of previously established theorems and previously accepted axioms, effectively the proof of the truth of a statement or expression

theoretical yield - quantity of product that would be obtained if the limiting reactant in a reaction reacted completely

theory - a well-established explanation of scientific data which can be disproven by a single contrary result

Theranostics: the association of a diagnostic test with a therapy The foundation of personalized medicine

thermodynamics - scientific study of heat, work, and related properties of mechanical and chemical systems

thermosetting plastic - a polymer that is made irreversibly rigid upon heating

thiol - an organic sulfur compound consisting of an alkyl or aryl group and a sulfur-hydrogen group; R-SH

thiol group - functional group containing a sulfur bound to a hydrogen, -SH

thorium - Thorium is the name for the element with atomic number 90 and is represented by the symbol Th

thulium - rare earth element with atomic number 69 with element symbol Tm

tin - metal with atomic number 50 and element symbol Sn

tincture - an extract of a sample into a solution, usually with alcohol as the solvent

titanium - transition metal with element symbol Ti and atomic number 22

Titanium is a useful transition metal

titrant - solution of known concentration used in a titration to determine the concentration of a second solution

titration - process of adding a known volume and concentration of one solution to another to determine the concentration of the second solution

topology: the field of mathematics concerned with spatial properties that are preserved under continuous deformations of objects (such as stretching, bending and morphing, but not tearing or gluing)

torr - unit of pressure equal to 1 mm Hg or 1/760 standard atmospheric pressure

trans isomer - isomer in which functional groups occur on opposite sides of the double bond

transcendental number: an irrational number that is “not algebraic”, i.e. no finite sequence of algebraic operations on integers (such as powers, roots, sums, etc.) can be equal to its value, examples being π and e. For example, √2 is irrational but not transcendental because it is the solution to the polynomial x2 = 2.

transfinite numbers: cardinal numbers or ordinal numbers that are larger than all finite numbers, yet not necessarily absolutely infinite

transition interval - concentration range of chemical species that can be detected using an indicator

transition metal - element from the B group of the periodic table characterized by having partially filled d electron orbital sublevels

Translation: A translation, also called a slide, is a geometrical movement in which a figure or shape is moved from each of its points the same distance and in the same direction

translational energy - energy of motion through space

transmute - to change from one form or substance into another

Transversal – A line which crosses two or more parallel or nonparallel lines in a plane.

Transversal: A line that crosses/intersects two or more lines

Trapezoid: A quadrilateral with exactly two parallel sides

Tree Diagram: Used in probability to show all possible outcomes or combinations of an event

Triangle – A three-sided closed figure. It contains three angles that when combined the sum equals 180°.

Triangle: A three-sided polygon

triangular number: a number which can be represented as an equilateral triangle of dots, and is the sum of all the consecutive numbers up to its largest prime factor – it can also be calculated as n(n + 1)⁄2, e.g. 15 = 1 + 2 + 3 + 4 + 5 = 5(5 + 1)⁄2

trigonometry: the branch of mathematics that studies the relationships between the sides and the angles of right triangles, and deals with and with the trigonometric functions (sine, cosine, tangent and their reciprocals)

Trinomial – An expression in algebra which consists of three terms.

Trinomial: A polynomial with three terms

trinomial: an algebraic equation with 3 terms, e.g 3x + 5y + 8z; 3x3 + 2x2 + x; etc

triple point - temperature and pressure at which the solid, liquid, and vapor phase of a substance coexist at equilibrium with each other

tungsten - transition metal with atomic number 74 and element symbol W

Two oxygen atoms bond to form an oxygen molecule

Tyndall effect - the scattering of a beam of light as is passes through a colloid

type theory: an alternative to naive set theory in which all mathematical entities are assigned to a type within a hierarchy of types, so that objects of a given type are built exclusively from objects of preceding types lower in the hierarchy, thus preventing loops and paradoxes

Typing: a method which can help in the assessment of the compatibility between two individuals, their organs, tissues or blood A technique used to characterize bacteria

Ultraviolet light is sometimes called black light because it's beyond the visible spectrum

ultraviolet radiation - ionizing electromagnetic radiation with a wavelength between 100 nm and 400 nm Sometimes called black light

UN ID - a four-digit code used to identify dangerous or flammable chemicals United Nations Identifier

UN number - a UN ID used for the transport of dangerous materials

Uniform: Term meaning "all the same" Uniform can be used to describe size, texture, color, design, and more

unit - a standard used for comparison in measurements

Unit: A standard quantity used in measurement Inches and centimeters are units of length, pounds and kilograms are units of weight, and square meters and acres are units of area

universal gas constant - usually indicated by R, the gas constant is the Boltzmann constant in units of energy per temperature per mole: R = 8.3145 J/mol·K

universal indicator - a mixture of pH indicators used to measure pH over a wide range of values

universal solvent - a chemical that dissolves most substances While water is often called the universal solvent, most nonpolar molecules are insoluble in it

Unknown – A symbol or letter whose value is unknown.

unsaturated - either refers to a solution that can dissolve more solute or to an organic compound containing double or triple carbon-carbon bonds

unsaturated fat - a lipid that contains no carbon-carbon double bonds

unsaturated solution - a solution in which solute concentration is lower than its solubility All solute present dissolves into the solution

uranium - element 92 with symbol U

vacuum - a volume containing little to no matter (no pressure)

valence - number of electrons needed to fill the outermost electron shell

valence bond theory - explanation of bonding between two atoms as a result of the overlap of half-filled atomic orbitals

valence electron - outer electron most likely to participate in bond formation or a chemical reaction

Valence Shell Electron Pair Repulsion Theory - molecular model that predicts geometry of atoms in a molecule by minimizing electrostatic forces between valence electrons around a central atom

Van der Waals forces - weak forces that contribute to intermolecular bonding

Van der Waals radius - half the distance between two unbonded atoms in a state of electrostatic balance

vanadium - Vanadium is the name for the element with atomic number 23 and is represented by the symbol V It is a member of the transition metals group

vapor - a condensable gas

vapor pressure - pressure exerted by a vapor in equilibrium with liquid or solid phases of the same substance or the partial pressure of a vapor above its liquid or solid

vaporization - phase transition from the liquid phase to gas phase

Variable – A symbol that stands for a number.

Variable: A letter used to represent a numerical value in equations and expressions Example: in the expression 3x + y, both y and x are the variables

vector - a geometric object that has both magnitude and direction

vector space: a three-dimensional area where vectors can be plotted, or a mathematical structure formed by a collection of vectors

vector: a physical quantity having magnitude and direction, represented by a directed arrow indicating its orientation in space

Venn diagram: a diagram where sets are represented as simple geometric figures (often circles), and overlapping and similar sets are represented by intersections and unions of the figures

Venn Diagram: A Venn diagram is usually shown as two overlapping circles and is used to compare two sets The overlapping section contains information that is true of both sides or sets and the non-overlapping portions each represent a set and contain information that is only true of their set

Venn diagram: a diagram where sets are represented as simple geometric figures (often circles), and overlapping and similar sets are represented by intersections and unions of the figures

Venous thrombosis: the formation of a blood clot in a vein It usually occurs in a vein of the lower limbs, in the leg or hip, rarely in the upper limbs

Vertex: The point of intersection between two or more rays, often called a corner A vertex is where two-dimensional sides or three-dimensional edges meet

Vertical angles – The opposite angles that are formed by the intersection of two lines. Vertical angles are equal.

Virus: a rudimentary infectious microorganism, containing a single type of nucleic acid encaged in a protein capsid, which uses the materials of the cell that it parasitizes to synthesize its own constituents It reproduces using just its own genetic material

viscosity - how readily a fluid flows, which is the ratio between an applied shear stress and the resulting velocity gradient

visible light - electromagnetic radiation that can be perceived by the human eye, usually from 380 nm to 750 nm (400 to 700 nm)

volatile - a substance that readily vaporizes

Volume – The amount which can be held, as measured in cubic units The volume of a rectangular prism = length times width times height

volume - the three-dimensional space occupied by a solid, liquid, or gas

Volume: A unit of measure describing how much space a substance occupies or the capacity of a container, provided in cubic units

volumetric flask - type of chemistry glassware used to prepare solutions of known concentration

Volumetric flasks are used to prepare chemical solutions

volume-volume percentage - v/v% is the ratio between the volume of a substance in a solution to the total volume of the solution, multiplied by 100%

VSEPR - see Valence Shell Electron Pair Repulsion Theory

water - a compound formed by one oxygen atom and two hydrogen atoms Usually this refers to the liquid form of the molecule

water gas - a combustion fuel that contains hydrogen gas and carbon monoxide

Water is called the universal solvent because so many compounds dissolve in it

water of crystallization - water the stoichiometrically bound in a crystal

water of hydration - water stoichiometrically bound in a compound, forming a hydrate

wavefunction - a function that describes the probability of the quantum state of a particle in terms of spin, time, position, and/or momentum

wavelength - the distance between identical points of two successive waves

wave-particle duality - the concept that photons and subatomic particles exhibit properties of both waves and particles

wax - a lipid consisting of chains of esters or alkanes derived from fatty acids and alcohols

weak acid - an acid that only partially dissociates into its ions in water

weak base - a base that only partially dissociates in water

weak electrolyte - an electrolyte that does not completely dissociate into its ions in water

wedge-and-dash projection - molecule representation using three types of lines to show three-dimensional structure

weight - the force on a mass due to the acceleration of gravity (mass multiplied by acceleration)

Weight: The measure of how heavy something is

Whole number – 0, 1, 2, 3, 4, 5, 6, 7, 8, etc

Whole Number: A whole number is a positive integer

word equation - a chemical equation expressed in words rather than chemical formulas

work - force multiplied by distance or the amount of energy needed to move a mass against a force

working solution - a chemical solution prepared for use in a lab, usually by diluting a stock solution

x: A symbol used to represent an unknown quantity in an equation or expression

X: The Roman numeral for 10

X-axis – The horizontal axis on a coordinate graph

X-coordinate – The first number in an ordered pair It refers to the distance on the x-axis

xenon - Xenon is an element with an atomic number of 54 and atomic weight of 131.29 It is an odorless inert gas that is used to fill cathode ray tubes

Xenon is often found in plasma balls

X-Intercept: The value of x where a line or curve intersects the x-axis

x-rays - X-rays are light rays with a wavelength from 0.01 to 1.0 nanometers Also Known As: X radiation

Yard: A unit of measure that is equal to approximately 91.5 centimeters or 3 feet

Y-axis – The vertical axis on a coordinate graph

Y-coordinate – The second number in an ordered pair It refers to the distance on the y-axis

yield - In chemistry, yield refers to the quantity of a product obtained from a chemical reaction Chemists refer to experimental yield, actual yield, theoretical yield, and percent yield to differentiate between calculated yield values and those actually obtained from a reaction

Y-Intercept: The value of y where a line or curve intersects the y-axis

ytterbium - Ytterbium is element number 70 with an element symbol Yb

yttrium - Yttrium is an element element with an atomic number of 39 and atomic weight of 88.90585 It is a dark gray metal that is used to make alloys for nuclear technology because the element has a high neutron transparency

Zermelo-Fraenkel set theory: the standard form of set theory and the most common foundation of modern mathematics, based on a list of nine axioms (usually modified by a tenth, the axiom of choice) about what kinds of sets exist, commonly abbreviated together as ZFC

Zeta function: A function based on an infinite series of reciprocals of exponents (Riemann’s zeta function is the extension of Euler’s simple zeta function into the domain of complex numbers)

zeta potential (ζ-potential) - the potential difference across the phase boundary between a liquid and a solid

zinc - Zinc is the name for the element with atomic number 30 and is represented by the symbol Zn It is a member of the transition metals group

Zinc is one of the transition metals

zirconium - Zirconium is the name for the element with atomic number 40 and is represented by the symbol Zr It is a member of the transition metals group

zwitterion - the dipolar amino acid formed when a hydrogen ion transfers from an acid group to an amine group

Alkalinity is a measure of how basic a substance is JazzIRT / Getty Images

salt - ionic compound formed by reacting an acid and a base; sometimes refers only to sodium chloride, NaCl

The flame test is an analytical technique used to help identify metal ions (c) Philip Evans / Getty Images

Zaitsev rule - rule in organic chemistry that states alkene formation from an elimination reaction will produce more highly substituted alkenes