Across
- 3. A scale from 0–14 that shows how acidic or alkaline a substance is
- 5. change : When a substance changes colour during a reaction
- 6. A substance that usually does not react like metals
- 7. A change that forms new substances and is usually not reversible
- 8. A solid that forms when two liquids react
- 11. A reaction that cannot be changed back
- 12. A substance made when an acid reacts with a base
- 14. A reaction between an acid and an alkali to make salt and water
- 15. A gas needed for burning and many reactions
- 16. A substance that burns to release energy
- 18. When a reaction makes bubbles of gas
- 20. A substance with pH less than 7 that can react with metals
- 23. A chemical that changes colour to show pH
Down
- 1. A process where substances change to form new substances
- 2. A reaction where a substance burns in oxygen
- 4. A substance with pH more than 7 that dissolves in water
- 9. Energy that is given out or taken in during a reaction
- 10. A rise or fall in temperature during a reaction
- 13. A substance that often reacts with oxygen or acid
- 17. A starting substance in a chemical reaction
- 19. A change where no new substance is made (e.g. melting)
- 21. A new substance made in a chemical reaction
- 22. A reaction where oxygen is added to a substance