| A | B |
|---|
| chemical reaction | a change in which one or more substances are converted into new substances |
| reactant | the substances that react in a chemical reaction |
| product | the new substance produced in a chemical reaction |
| chemical equation | a way to describe a chemical reaction using chemical formulas and other symbols |
| coefficient | numbers to the left of the reactants and products; represents the number of units of each substance taking part in a reaction |
| balanced chemical equation | when the number of atoms of each element on both sides of an equation is the same |
| combustion reaction | occurs when a substance reacts with oxygen to produce energy in the form of heat and light |
| synthesis reaction | when two or more substances combine to form another substance |
| decomposition reaction | occurs when one substance breaks down, or decomposes, into two or more substances |
| single-displacement reaction | when one element replaces another element in a compound |
| double-displacement reaction | when the positive ion of one compound replaces the positive ion of the other to form two new compounds |
| precipitate | an insoluble compound that comes out of solution during a reaction |
| oxidation | the loss of electrons |
| reduction | the gain of electrons |
| exergonic reaction | chemical reactions that release energy |
| exothermic reaction | when the energy given off by a reaction is primarily in the form of thermal energy or heat |
| endergonic reaction | a chemical reaction in which more energy is required to break bonds than is released when new ones are formed |
| endothermic reaction | when energy is needed and absorbed in the form of thermal energy |
| catalyst | a substance that speeds up a chemical reaction without being permanently changed itself |
| inhibitor | substances used to slow down a chemical reaction |
