Across
- 2. substances that undergo a chemical change
- 5. amount of a substance in a given volume
- 7. _____change: any change that alters the form or appearance of a substance without changing it into a different substance
- 9. biological catalysts that help speed up chemical reactions
- 10. number placed in front of chemical formula in equation
- 12. new substances that form in a chemical reaction
- 16. _____replacement: when a single element replaces another single element in a compound
- 17. material used to decrease rate of chemical reaction
- 18. increases the reaction rate by lowering the activation energy needed
Down
- 1. _____replacement: when two elements exchange places in a reactions
- 3. _____ change: change of matter that produces new substances
- 4. _____energy: minimum amount of energy needed to start a chemical reaction
- 6. _____system: matter can enter from or escape to the surroundings
- 8. solid that forms from liquids during a chemical reaction
- 9. _____reaction: reaction that releases energy
- 11. _____reaction: reaction that absorbs energy
- 13. reaction when compounds break down into simpler substances
- 14. two or more elements combine to make a more complex substance
- 15. _____system: matter does enter or leave