VOCAB

4. a substance that slows, or even stops, a chemical reaction
6. minimum amount of energy needed to start a chemical reaction
7. a chemical reaction that releases thermal energy
9. a type of chemical reaction in which the negative ions in two compounds switch places, forming two new
10. a starting substance in a chemical reaction
12. a catalyst that speeds up chemical reactions in living cells
15. a substance that increases reaction rate by lowering the activation energy of a reaction
16. law that states that the total mass of the reactants before a chemical reaction is the same as the total mass of the
17. a description of a reaction using element symbols and chemical formulas

1. a process in which atoms of one or more substances rearrange to form one or more new substances
2. a type of chemical reaction in which one compound breaks down and forms two or more substances
3. a substance produced by a chemical reaction
5. a type of chemical reaction in which one element replaces another element in a compound
8. a chemical reaction that absorbs thermal energy
11. a type of chemical reaction in which two or more substances combine and form one compound
13. a number placed in front of an element symbol or chemical formula in an equation
14. a chemical reaction in which a substance combines with oxygen and releases energy