Across
- 2. an easy way to show a chemical reaction
- 3. when energy is released in the form of heat
- 7. a rapid reaction between oxygen and a substance called fuel
- 8. the substances you have at the beginning
- 9. the number in front of a chemical formula in an equation
- 10. a characteristic of a substance that describes its ability to change into other substances
- 12. a material that increases the rate of a reaction by lowering the activation energy
- 13. biological catalysts in the cells of your body
- 14. is a characteristic of a substance that can be observed without changing the substance into another substance
- 16. anything that has mass and takes up space
- 17. a material that releases energy when it burns
- 19. a solid that forms from solution during a chemical reaction
- 20. states that during a chemical reaction, matter is not created or destroyed
- 21. the amount of a substance in a given volume
- 22. a material used to decrease the rate of a reaction
- 24. when two or more elements or compounds combine to make a more complex substance
- 25. matter is not allowed a way to enter or leave
Down
- 1. when energy is absorbed
- 4. a change in matter that produces one or more new substances
- 5. a change that alters the form or appearance of a substance
- 6. the new substances
- 7. the study of matter and how matter changes
- 11. when one element takes the place of another
- 15. the minimum amount of energy needed to start a chemical reaction
- 18. breaks down compounds into simpler products
- 23. matter can enter from or escape to the surroundings.