click below
click below
Normal Size Small Size show me how
Chemical reactions
Term | Definition |
---|---|
chemical reaction | A process in which atoms of one or more substances rearrange to form one or more new substances. |
chemical equation | A description of a reaction using element symbols and chemical formulas. |
reactants | The starting substances produced by the chemical reaction. |
products | The substances produced by the chemical reaction. |
law of conservation of mass | States that the total mass of the reactants before a chemical reaction is the same as the total mass of the products after the chemical reaction. |
coefficient | A number placed in front of an element symbol or chemical formula in an equation. |
decomposition | One compound breaks down and forms two or more substances. |
endothermic reaction | Chemical reactions that absorb thermal energy. (cold) |
exothermic reaction | Chemical reaction that releases thermal energy. |
What happens during a chemical change? | A NEW substance is produced. |
what happens during a physical change? | The original substance still exists but physically is changed. |
Precipitate | a solid formed from a liquid during a chemical reaction |