Across
- 2. natural fuel such as coal or gas
- 6. set of compounds that involve nitrogen and oxygen molecules
- 7. evaporated water turned into clouds
- 9. a liquid necessary for life in a cycle
- 10. process in which carbon atoms continually travel
Down
- 1. a form of liquid falls from clouds
- 3. a process in which water travels upward
- 4. how nitrogen is released to start cycle again
- 5. a necessary element in the 3 cycles
- 8. which nitrogen passes successively from air to soil to organisms and back to air or soil