| A | B |
|---|
| mole | a quantity of 6.02 X 10(23) units of substance equal to the sum of the atomic masses in grams: Avogadro's number |
| formula mass (MA) | the sum of the atomic masses of a substance in a.m.u. |
| gram formula mass (GFM) | the sum of atomic masses of a substance in grams |
| coefficient | the integer that appears in front of an element, molecule, or compound indicating the number of moles present |
| subscript | the integer to the lower right of an element that indicates the number of atoms present in the compound |
| species | the individual products and reactants in a chemical reaction |
| law of conservation of mass | in any chemical reaction, mass can neither be created nor destroyed; the mass of the reactants must be equal to the energy of the products |
| balanced equation | a chemical reaction in which the number of moles of each element on the reactants side is equal to the number of moles of each element on the products side |
| synthesis reaction | a chemical reaction in which two or more substances combine to form a compound |
| decomposition reaction | a chemical reaction in which a compound is broken down into similar substances |
| single-replacement reaction | a chemical reaction in which a metal replaces a metal OR a nonmetal replaces a nonmetal within a compound |
| double-replacement reaction | a chemical reaction in which a metal replaces a metal AND a nonmetal within two compounds; two compunds "trade" elements |
| molecular formula | formula for a compound which provides the number and identitiy of the atoms of each element present |
| empirical formula | formula for a compound which provides the simplest ratio of the elements present |
| percent mass | % composition by mass=mass of part/mass of whole X 100 |
