Across
- 2. during a chemical reaction, matter is not created or destroyed.
- 5. a characteristic of a substance that can be observed without changing the substance into another substance.
- 7. use chemical formulas and other symbols instead of words to summarize reaction.
- 9. a material that increases the rate of a reaction by lowering the activation energy.
- 11. a reaction that releases energy in the form of heat.
- 13. the result of fire
- 14. a characteristic of a substance that describes its ability to change into other substances.
- 19. the cells in your body contain biological catalysts.
- 20. a material that releases energy when it burns
- 23. matter is not allowed to enter or leave.
- 24. can be described in the terms of two kinds of properties, physical and chemical.
- 25. a material that used to work by preventing reactants from coming together.
- 26. the minimum amount of energy needed to start a chemical reaction.
Down
- 1. a number placed in front of a chemical formula in am equation
- 3. the study of matter and how matter changes
- 4. a solid that forms from solution during a chemical reaction
- 6. when the reaction is complete, you have new substances.
- 8. A change in matter that produces one or more new substances
- 10. the amount of a substance in a given volume
- 12. a reaction in which energy is absorbed
- 15. any change that alters the form or appearance of a substance but that does not make the substance into another substance.
- 16. breaks down compounds into simpler products.
- 17. matter can enter from or escape to surroundings.
- 18. when two elements in different compounds trade places.
- 21. the substances you have at the beginning.
- 22. when two or more elements or compounds combine to make more complex substances.