Activity 2

3. the outer mantle of the solid earth.
4. a pure substance
5. A solution with a pH lower than 7
7. concentration of hydronium ions in a solution
9. a substance that forms because of a chemical reaction
13. comprises all types of water resources
16. rate at which energy is used
18. A widely accepted hypothesis that stands the test of time.
19. A test that is used to rule out a hypothesis or validate something already known.
22. anything that takes up space and has mass.
23. is a substance that consists of two or more elements

1. is the smallest particle of an element
2. sum of all the biochemical reactions in an organism
6. suggested explanation based on evidence that can be tested by observation or experimentation.
8. named after James Prescott Joule
9. The vast majority of our people directly dependent on the natural resources of their country for their basic needs
10. Where life operates.
11. main element in organic compounds
12. A solution with a pH higher than 7.
14. Developing new knowledge based upon old knowledge.
15. done when force is applied to an object over a distance
17. a substance that starts a chemical reaction
20. The study of the interactions between life and its physical environment.
21. the ability to do work