Advertisement Upgrade to remove ads


the study of matter and the changes it can undergo

scientific method

experiments prove disprove
publication further experiments

basic science

research without the goal of a practical application

applied science

research with well defined, short terms goals for a specific problem


application of science for industrial production and societal goals


large enough to be visible to the naked eye


too small to be seen except under a microscope


cannot see even w/ microscope; atoms and molecules


is a measure of the amount or quantity of matter in an object


is the force that results from the attraction between matter and the earth

intensive property

properties that are independent of the amount of the sample

extensive property

depends on the size of the sample


a pure substance consisting of only one kind of atom (ex copper) and can't be decompressed into simpler substances by normal chemical means


smallest unit of an element

chemical compound

pure substances composed of atoms of different elements combined in definite, fixed ratios. And can be decomposed into simpler substances or elements by chemical means


flammable when burned in the presence of oxygen


uniform in composition (milk)


not uniform in compostion (water and oil)

chemical property

properties that result in a chemical reaction converting the identity of one or more of the substances (flammability, anti-inflammatories, biodegradable)

physical property

properties that can be observed or measured with out changing the identity of the substances (boiling point, melting point, density, color)

chemical change

process in which one or more pure substances are converted to one or more different pure substances

physical change

process where the identity of the substance remains intact


substances formed as the result of a chemical reaction


the smallest unit fo a chemical compound; the simplest structural unit of an element or compound

molecule compound

c, a chemical compound whose simplest units are molecules


the capacity of doing work or causing change

potential energy

energy in storage by virtue of position or arrangement

kinetic energy

the energy of objects in motion


in a chemical formulas, numbers written below the line to show numbers or ratios of atoms in a compound


in a chemical equation are the numbers written before formulas to balance the equation


describes information or experiments that are numerical


describes information or experiments that are not numerical

unit conversion factor

a fraction in which the numerator is a quality equal or equivalent to the quantity in the denominator, but expressed in different units


is the term used to express the agreement of the measured value with the true value of the same quantity


expresses the agreement among repeated measurements

atomic number

the number of proton in the nucleus of an atom (bottoms left number)

mass number

is the sum of the numbers of protons and neutrons in the nucleus (top left number


electrically charged atoms that have gained or lost electrons.

atomic mass unit

the unit of relative atomic massess of the elements

atomic weight

the number that represents the (weighted average) atomic mass of the isotopes in a given element (bottom number)

atomic orbitals

the regions around the nucleus within which the electrons have the highest probability of being found


In the electron configuration they are s (2 e- and 1 orbital), p (6 e- and 3 orbitals), d (10 e- and 5 orbitals) and f (14 e- and 7 orbitals)

aufbau principle

an electron occupies the lowest-energy orbital that can receive it

valence orbitals

orbitals that contain the outer-shell electrons of an atom

valence electrons

electrons on the outermost energy level of an atom


element that conduct electric current; most are malleable and ductile


elements that do not conduct electrical currents


metalloid elements with electrical conductivity intermediate between that of metals and nonmetals. Used in solid-state electronics

alkaline earth metals

reactive but not has much as alkali metals group 2


for metals is related to size, the larger the atom the more reactive it becomes, for nonmetals the opposite is true

Henri Becquerel

experimented with phosphorescence of certain minerals

Earnest Rutherford

Found that alpha rays could be stopped by thin pieces of paper. Whereas beta rays were only stopped by at least .5cm of lead

Paul Villard

discovered the high energy, extremely penetrating gamma ray having characteristics of light waves. Very damaging to human issue.


the result of a natural change of an isotope of one element into an isotope of a different element resulting in a nuclear reaction.

radio cardon dating

determining the age of a sample using carbon-14 isotope

food radiation

retards the growth of organisms such as molds,bacteria, and yeasts


radioisotopes are inserted into patients body allowing na image to be produced of the problem area.

binary compound

chemical compound composed of one metal and one nonmetal

bonding pair

pair of electrons shared between 2 atoms in a molecule

nonbonding pair

unshared pair of valence electrons in a molecule

lewis dot symbols

the valence electrons, represented by dots, are placed around the symbol until they are used up or unti all 4 sides are occupied

single covalent bond

hydrogen atoms share their single electron giving them an electron configuration like helium


compounds containing only carbon and hydrogen


hydrocarbons with carbon-carbon single bonds

saturated hydrocarbons

hydrocarbons that are alkanes

hydrocarbon single bonds

one carbon and 4 hydrogen atoms will share electrons to achieve noble gas configuration

double bond

a bond in which 2 pairs of electrons are shared between atoms

triple bond

a bond in which 3 pairs of electrons are shared between atoms


describes a bond or molecule in which charge is evenly distributed, with no positive or negative regions


describes a bond or molecule in which charge is unevenly distributed, creating positive and negative regions. Based on differences in electronegativity.


a compound that conducts electricity when melted or dissolved in water


a compound that does not conduct electricity when melted or dissolved in water, or does not separate into ions in water

intermolecular forces

attractive forces that act between molecules; weaker than covalent bonds

dipole-dipole forces

attractive forces between polar molecules

hydrogen bonding

attraction between a hydrogen atom bonded to a highly electronegative atom (O, N, F) and an electronegative atom in another r the same molecule


Fixed shape and fixed volume, non-compressible, very strong intermolecular


variable shape but fixed volume, compressible, weak intermolecular forces

reaction rate

amount of reactant converted to product in a specific amount of time

activation energy

Quantity of energy needed for successful collision of reactants; determines reaction rate.

dynamic equilibrium

a state of balance between opposite changes occurring at the same rate

chemical equilibrium

condition in which a chemical reaction and its reverse are occurring at equal rates

physical equilibrium

when the rate at which a substance changes between physical states is constant

Le Chatelier's principle

When a stress is applied to a system at equilibrium, the equilibrium shifts to relieve the stress


(of a chemical reaction or compound) occurring or formed with the release of energy as heat


(of a chemical reaction or compound) occurring only with energy as heat from an external source


a measure of the disorder of matter. If a change in entropy results in a more disordered state the entropy is said to be positive


the science of energy as heat and its transformation

First Law of Thermodynamics

energy can be converted from one form to another but cannot be created or destroyed

Second Law of Thermodynamics

The total entropy of the universe is constantly increasing


the gain of oxygen, the loss of hydrogen, or the loss of electrons


the loss of oxygen, the gain of hydrogen, or the gain of electrons


two or more compounds with the same molecular formula but different arrangements of atoms

structural isomers

isomers that differ in the order in which the atoms are bonded together

alkyl groups

alkanes with hydrogen atom removed and are attracted to a straight chain hydrocarbon


hydrocarbons with one or more carbon-carbon double bonds


are classified by the reactions by which they were formed

addition polymers

when all atoms in the monomers are incorporated into the polymer

condensation polymer

a polymer formed by repeated condensation reactions of one or more monomers


produced the ethylene


is a polymer made from a molecule with 2 carboxylic acid and a molecule with 2 alcohols


is a polymer made from a di-acid and a di-amine


organic compounds containing a hydroxyl (OH) functional group

functional group

atom or groups of atoms in a molecule that gives the substance a characteristic chemical behavior


organic compounds containing a -CHO functional group

carboxylic acids

organic compounds containing a -COOH functional group


organic compounds containing a -C=O (carbonyl) functional group between two carbon atoms


are reduced forms of matter which burn easily in the presence of oxygen producing large quantities of heat


is a form of energy which can be used to do work

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording