- activity series of metals: lits metals in order of decreasing reactivity
- alkali metals: any metal in group 1A on the periodic table
- alkaline earth metals: any metal in group 2A on the periodic table
- alpha particles: contain two protons and two neutrons and have a double positive charge
- alpha radiation: consists of helium nuclei that have been emitted from a radioactive source,
- atom: smallest particle of an element that retains the properties of that element
- Atomic mass: the weighted average of the masses of the isotopes of an element
- atomic number: the number of protons iin the nucleus of an atom represented by the letter Z
- avogadro's number: 6.02 X 10^23
- band of stability: the stable nuclei on a neutron-vs-proton plot
- beta particles: a fast moving electrons emitted from a certain radioactive nuclei, it is formed when a neutron decomposes
- beta radiation: fast-moving electron emitted from certain radioactive nuclei, it is formed when a neutron decomposes
- boling point: temperature at which the vapor pressure of the liquid is just equal to the external pressure
- catalyst: a substance that speeds up a reaction without being used up
- Chemical properties: describes chemical changes. ex - rust, rot, decay
- Chemical property: the ability of a substance to undergo chemical reactions and to form new substances
- coefficients: a small whole number ratio that appears in front of a formula in an equation
- compound: a substance that can be seperated into simpler substances only by chemical reactions
- control rod: a steel or aluminum rod that can be moved up or down to control the rate of the nuclear reaction
- crystals: atoms, ions, or molectules are arranged in an orderly repeating three dimensional pattern
- Daltons Atomic Theroy: a) all substancs were composoesd of tiny invinsible particles called atoms. b) atoms of the same element are identical. The atoms of any one element are different thant hose of any other element. c) Atoms of different elements can combine with one another in whole number ratios to compounds. d) chcemical reactions occur when atoms are seperated, joined, or rearranged
- density: mass over volume
- electrons: the atomic#, equal to protons, negitivly charged substance particle
- element: a substance that cannot be changed into a simpler substance under normal laboratory conditions
- empirical formula: lowest whole number ratio of the elements in a compound
- evaporation: vaporization of an uncontained liquid
- fission: splitting of a nucelus into smaller fragments
- fusion: a reaction in which two light nuclei combine to produce a nucleus of heavier mass, accompained by the realease of a large amount of energy
- gamma radiation: electromagnetic radiation
- gas: shape+volume of container
- half life: the time requred for one half of the atons of a radioisotope to emit radiation and to decay to products
- Halogens: gasses within group 7A
- heterogenous mixture: not uniform in composition. ex-soil, fruit salad, dirt
- homogenous mixture: uniform composition. ex toothpaste, bronze
- Ion: atoms or groups of atoms that have a positive or negative charge
- isotope: atoms of the same element with a different mass
- Law of conservation of masss: in any physical or chemical reaction mass is neither created nor destroyed
- liquid: shape of container and volume
- mass: amount of matter
- mass #: protons + neutrons
- matter: takes up space
- mixture: a combination of two or more substances that are not chemically combined
- molar mass: mass of one mole of any element or compound
- Mole: 6.022 X 10^23 representative particles of a substance
- molecular formula: a chemical formula that shows the actual number and kinds of atoms present in a molecule of a compound
- monatomic ion: an ion formed from a single atom.
- neutrons: mass - protons, subatomic particle with no change
- noble gasses: any member of a group of gaseous elements in group 0 of the periodic table; the s and p sublevels of their outermost energy level are filled
- nuclear reaction: a process that alters the energy or structure or composition of atomic nuclei
- nuclear reactor: A device where a chain reaction is maintained and controlled for the production of nuclear energy or radioactive isotopes.
- percent mass: mass of a certain element compared to the mass of the compound
- periodic table: elements that are arranged in rows and colums according to similarities in their properties
- photon: a quantum of light; a discrete bundle of electromagnetic energy that behaves as a particle
- physical changes: alters substance without changing composition. ex-melt, freeze, oil, condense, crush
- physical property: observed or measured wthout changing composition
- polyatomic ion: tightly bound groups of atoms that behave as a unit and carry a charge
- protons: the atomic #, equal to electrons, positivly charged substance particle
- solid: definite shape-volume
- solution: homogeneous mixture
- STP: 0 degrees C.
- sublimination: the change of a substance from a solid to a gas or vapor without passing through the liquid state
- substance: mater that has uniform and definite composition
- transition metals: the b group elements, innder transition mentals or rare earths
- vapor gas: gas that usually a liquid or a solid at room temperature
- vapor pressure: vaporized particles collide with the walls of a sealed containor