WATER!

3. The breaking down of rocks, soil, and minerals.
6. To become mixed into a liquid so as to form a solution.
7. The property of having a pair of opposite charges on a molecule.
9. The principle that the same natural laws and processes that operate in the universe now, have always operated in the universe in the past and apply everywhere.
10. The process that involves water expanding when it freezes, thus breaking rocks apart. A type of mechanical weathering.
12. The process of iron combining with water and oxygen to form a red color on metals.
14. Characteristic of a material that allows liquids or gases to pass through it easily using little holes or spaces.
15. The ability of a liquid to flow in narrow spaces against gravity, so that plants can transfer water from the roots to the leaves.
16. The force that makes the top layer of a liquid stretch tight like a film.

1. The force of attraction between different kinds of molecules (including water).
2. The average atmospheric conditions and variation at a particular place over a long period. The rate of weathering depends on this.
4. The sticking together of particles of the same substance (like water).
5. Type of weathering related to substances and the changes they undergo due to interactions between atoms or molecules.
8. The process of scraping or wearing something away. A type of mechanical weathering.
11. The process by which natural forces move weathered rock and soil from one place to another.
13. Type of weathering related to the physical breakdown of substances.