Hydrosphere

3. conserving and protecting something valuable, such as the planet, its ecosystems and natural resources.
5. The bottom layer of the ocean
6. Cycling of water on Earth through a variety of processes
9. All the water on or surrounding the surface of the planet
14. A measure of how suitable water may be for drinking
15. Any substance above 7 on the pH scale
18. The process of purifying or clarifying water to make it more potable.
19. Type of marine ecosystem that is controlled by the movement of tides
20. The middle layer of the ocean

1. Cloudy or opaque; due to stirred up sediment or particles within the water
2. Oxygen found in a body of water
4. The scale that is used to identify acids and bases
7. A liquid that dissolves substances called solutes
8. Valuable water resource on Earth; provides drinking water
10. refers to the amount of salt contained within a solution.
11. When less-dense surface water is replaced by cold, denser, more nutrient-rich water from below
12. The area of land where surface water drains when the ground is unable to absorb it
13. The area of land drained by a river and its branches
16. Underground rock layer that contains a vital source of water for human consumption and use.
17. Where a river's current meets the ocean and acts as a marine habitat
21. Any substance below 7 on the pH scale