Across
- 4. number placed in front of a chemical formula
- 5. when two or more elements combine to make more complex substance
- 7. reaction that breaks down compounds
- 10. reaction that is complete
- 11. reaction which releases energy
- 13. a systen in which no matter can enter
- 14. decrease the rate of a reaction
- 15. rapid reaction
- 16. reaction which energy is absored
- 19. mimimum amount of energy needed is a chemical reaction
Down
- 1. substances in the beginning
- 2. cells in your body
- 3. the study of matter and how matter changes
- 4. amount of a substance ina given volume
- 6. material that releases energy when it burns
- 8. solid that forms from solution
- 9. when one element replaces another in a compound
- 12. a system in which matter can enter
- 17. Anything that has mass
- 18. increses the rate of a reaction