Across
- 3. chemical reaction that gives off heat energy
- 7. a process that changes substances into new substances
- 10. a material with a particular chemical makeup
- 11. a chemical reaction that absorbs energy
- 12. a change in the matter that doesn't affect it's chemical composition
- 13. to act because of something that happened
- 14. one of the six elemental gases that doesn't naturally react with other elements
Down
- 1. the smallest unit of an element that has all the chemical properties of that element
- 2. the ability to do work or cause change, can be changed into different forms and can move between objects
- 4. a substance that has a unique composition and the properties; it may exist as a solid, liquid, or gas
- 5. a process in which nitrogen in the atmosphere enters the soil and becomes part of living organisms then eventually returns to the atmosphere
- 6. interaction between molecules that cause a chemical change, converting an existing substance into a new one
- 8. the path or orbit electrons follow around the nucleus of an atom
- 9. the physical matter of which living or nonliving things are composed