atom |
The smallest unit of an element that has the properties of that element. |
molecule |
A group of two or more atoms that are joined chemically. |
element |
A substance made of only one kind of atom. |
change of state |
A physical change that occurs when matter changes from one state to another, such as from a liquid to a gas. |
physical change |
A change in which a substance remains the same substance. |
mixture |
A combination of two or more different substances. |
physical property |
A trait-such as color, shape, or hardness-that describes a substance by itself. |
chemical property |
A property that involves the ability of a substance to react with other materials to form new substances. |
chemical change |
A change in which a substance or two becomes a new substance or two. |
chemical reaction |
A change in which one or more new substances are formed. |
compound |
A substance made of two or more different elements. |
law of conservation of mass |
The mass of the products of a chemical reaction equals the mass of the reactants. |