Across
- 4. the burning of fuels, such as wood, or oil
- 6. added to food to prevent spoiling
- 8. a type of protein that speeds up chemical reaction in a living thing
- 10. hand warmers use ___ energy
- 11. minimum energy required to start a chemical reaction
- 12. increasing the ____ can be dangerous if it speeds up a reaction
- 14. Hydrogen and Oxygen can react to form __
- 15. a spark most likely ignited ___ and destroyed the airship
Down
- 1. when a banana or an avocado turn brown
- 2. draw energy from the surroundings, and leave an area feeling cold
- 3. airship destroyed by flames in New Jersey
- 5. chemical reactions using enzymes require __ activation energy
- 7. material used to decrease the rate of a chemical reaction
- 9. increases the reaction rate
- 13. the amount of a substance in a given volume