Across
- 3. the spheres in the solar system.
- 5. remains of plants and animals
- 6. invisible gas surrounding the earth.
- 8. the uppermost layer of something.
- 11. removal of trees
- 12. Provides light and heat to earth.
Down
- 1. seasonal movement.
- 2. colorless, odorless gas
- 3. harmful materials in the environment
- 4. an oxide containing two atoms of oxygen
- 7. Opposite of cool.
- 9. emission of energy.
- 10. the chemical element of atomic number 6