Across
- 2. Is a vital gas to survive.
- 5. A liquid or gas that is used to remove heat from something.
- 6. gas produced by burning carbon, organic compounds and by respiration.
- 9. It is a layer of gases that is around the earth or other planets.
- 11. Is a vital liquid to living beings.
Down
- 1. A chemical element, its a gas unreactive.
- 3. It is a substance in a gaseous state
- 4. Which is first or older than anything else.
- 7. Is a planet that we live.
- 8. A mountain with a large hole at the top through which magma, rocks and gases are thrown, sometimes they are forced.
- 10. Is a living being that purifies oxygen.