Across
- 2. air pollution that reduces visibility
- 4. term for non-renewable energy sources such as coal
- 7. the process of collecting and processing materials
- 8. anything that surrounds us
- 9. form of precipitation with acidic components, such as sulfuric or nitric acid
- 10. to make dirty and not safe or suitable to use
Down
- 1. the act of protecting Earth's natural resources
- 3. the ability of things to get disintegrated (decomposed) by the action of micro-organisms
- 5. energy that does not come from fossil fuels
- 6. an odorless, colorless gas made up of three oxygen molecules