Question | Answer |
absorption spectrum | electromagnetic radiation that has passed through a medium in which radiation of certain frequencies is absorbed |
acceleration | the change in velocity divided by time (a = _v / _t) |
accuracy | values such as density of a specific element that are accepted norms and usually published; if a measurement taken matches accepted norms or a standard value, it is said to be accurate |
acid/base reaction | a chemical reaction where an acid and base are the reactants and a salt and water are the products, often called neutralization |
acids | a substance that in solution donates a proton (pH less than 7) |
alpha radiation | a form of radiation that consists of a helium nuclei that can be emitted from the nuclei of an atom and can be stopped by a thin sheet of paper |
atomic mass unit (AMU) | a unit of measurement defined as 1/12 the mass of a carbon-12 atom |
amplitude | the measurement of the distance from the resting point in a wave to either the crest or trough of that wave |
anion | a negatively charged ion; symbol placed in the second position when writing the formula of a chemical compound |
atomic nucleus | comprised of all the protons and neutrons in the center of an atom, occupying a tiny amount of the space and containing the majority of the mass within an atom |
atomic number | number of protons in an atom |
base | a substance that in solution accepts a proton (pH greater than 7) |
base/acid reaction | a chemical reaction where an acid and base are the reactants and a salt and water are the products, often called neutralization |
beta radiation | a form of radiation that consists of an electron or positron that may be emitted from the nuclei and can be stopped by aluminum foil |
bias | a mind set that leads the researcher to base their hypotheses or conclusions on a narrow range of variables discounting other plausible ones |
binding energy | the energy that holds an atomic nucleus together, measured by the force that must be overcome to split the nucleus (fission) resulting in a nuclear reaction |
cations | a positively charged ion; symbol placed in the first position when writing the formula of a chemical compound |
chemical bonds | any of a number of strong attractive forces produced by electron interactions; e.g. covalent, ionic, metallic |
chemical precipitation | the formation of a solid from a solution |
chemical reaction | a process in which the atoms of one or more substances are rearranged into new substances |
coefficient | whole numbers written in front of individual compounds or atoms within a chemical equation indicating the relative amounts of each for the purpose of balancing the equation |
combustion reaction | a chemical reaction using oxygen and producing heat and/or light |
compression/longitudinal waves | waves that have vibrations along or parallel to their direction of travel |
concentration | a measure of the amount of dissolved substance contained per unit of volume |
conductor | any matter that allows the flow of electrical current or heat |
Coulomb's law | the principle that the force between two point charges acts in the direction of the line between them and is directly proportional to the product of their electric charges divided by the square of the distance between them |
covalent bond | type of chemical bond where electrons are shared |
current | the rate of flow, as in electrical charges or water |
decomposition reaction | a chemical reaction in which a single compound reacts to produce two or more products (AB‡ A + B) |
density | amount of mass per volume of a given amount of matter |
diffraction | the bending of a wave around a barrier |
dispersion | separation of a wave or radiation into its individual components like separation of light into colors by a prism |
dispersion forces | weak forces between atoms or molecules resulting from the movement of electrons in the electron cloud around the system |
effervescence | bubbling of a solution due to the escape of a gas either produced by a chemical reaction or a gas coming out of solution as in a carbonated beverage |
electricity | current generated by the flow of electrons through a circuit |
electromagnetic force | a fundamental force arising from the attractions and repulsions of the magnetic and electrical fields |
electromagnetic radiation | a form of energy with wave properties which can travel through a vacuum at a characteristic speed of 3.00 X 108 meters per second |
electron configuration | specific arrangement of electrons in the orbitals of an atom |
electronegativity | a measure of the tendency of an atom to attract electrons |
emission spectrum | the range of electromagnetic radiation produced by a source |
energy level | one of a quantized series of states of the electrons within an atom separated from others in the series by distinct quantities of energy |
entropy | measure of the randomness in a system |
first law of thermodynamics | law stating the change of energy of a system is equal to the heat transferred minus the work done |
first order rate | the rate of decay is proportional to the concentration raised to the first power; there is a negative linear relationship between the log of the sample isotope concentration versus time |
frequency | 1. in general use, the number of regularly occurring events per unit of time 2. the number of wavelengths that pass any fixed point per second, often expressed in hertz |
fundamental force | any of four forces that act between bodies of matter and that are mediated by one or more particles; in order of decreasing strength: the strong force, the electromagnetic force, the weak force, and gravity |
gamma radiation | form of radiation emitted from the nucleus in high energy waves; may be blocked by a thick layer of lead |
gas | state of matter without a definite shape or volume |
gravitational force | fundamental force that tends to draw two masses together, increasing as the masses are increased or distance between them is decreased |
gravitational potential energy | the amount of stored energy an object has based on its position relative to Earth (GPE = mgh) |
ground state | position of an electron in its lowest possible energy level within an atom |
group | vertical column on the Periodic Table; also known as a family |
heat | energy transfer between two objects of different temperature |
hydrogen bonding | bond formed when hydrogen in a molecule is attracted to a more electronegative atom, such as oxygen or nitrogen, in another molecule |
induced dipole interaction | temporary condition in which the positive part of a polar molecule attracts the negative part of another molecule |
inhibitor | substance that prevents or slows down a chemical reaction or resists the transfer of heat or electricity |
interference | when two or more waves combine to produce a new wave; constructive interference is when the waves add to produce a greater amplitude; destructive interference is when the waves add to produce a smaller amplitude |
intermolecular attraction | force of attraction between two or more molecules that produces a weak bond |
ion | electrically charged atom or group of atoms formed by the loss or gain of one or more electrons |