Across
- 4. a reaction that absorbs energy in the form of heat
- 7. a solid that forms from a solution during a chemical reaction
- 8. a material that decreases the rate of reaction
- 9. anything that has mas and occupies space
- 11. a short easy way to show a chemical reaction
- 14. a substance that enters into a chemical reaction
- 15. a characteristic of a substance that can be observed without changing the substance into another substance
- 16. a system in which matter can enter from or escape to the surroundings
- 17. a substance formed as a result of chemical reaction
- 19. a biological catalyst that lowers the activation energy of reactions in cells
- 22. a change that alters the form or appearance of a material but does not make the material into another substance
- 23. the study of matter and how matter changes
Down
- 1. a rapid reaction between oxygen and fuel that results in fire
- 2. a reaction that releases energy in the form of heat
- 3. the minimum amount of energy needed to get a chemical reaction started
- 5. a characteristic of a substance that describes the ability to change into different substances
- 6. the principal stating that matter is not created or destroyed during a chemical reaction
- 10. a reaction in which one element replaces another in a compound or when two elements in different compounds trade places
- 12. the amount of one material in a certain volume of another material
- 13. a material that increases the rate of reaction by lowering the activation energy
- 18. a system in which no matter is allowed to enter or leave
- 20. a material that releases energy when it burns
- 21. a number infront of a chemical formula in an equation