Across
- 3. a change in which a new substance is formed
- 4. the energy required to start a chemical reaction
- 6. some chemical changes require the presence of another substance which itself does not undergo any change
- 7. the substance formed after a chemical reaction
- 8. we get this when we burn something
- 9. initial substances after a chemical reaction
Down
- 1. a change in which no new substance is formed
- 2. the increase in size of matter on heating
- 5. the decrease in size of matter on cooling