Across
- 4. a substance that can make air, soil, or water harmful to organisms and structures
- 5. air quality index
- 9. the measure of the average speed of particles of matter
- 11. I have 6 protons
- 17. most of the earth's atmosphere is made of this
- 18. the amount of "stuff" something contains
- 19. a type of particulate matter
- 20. the chemical symbol for a toxic liquid element used in thermometers
- 21. matter that has a definite volume but not a definite shape
- 23. also known as burning
- 24. containing substances that cause harm to people, plants, animals, and structures.
- 25. when sulfur dioxide mixes with water you get _____ acid.
Down
- 1. fuel and oxygen are both _____ in a combustion readilutepm parts per million
- 2. a negatively charged sub-atomic particle
- 3. anything that has volume and has mass
- 5. the basic building block of matter
- 6. a sub-atomic particle with a neutral charge
- 7. a fossil fuel made from ancient forests
- 8. the simplest type of substance made of identical atoms
- 10. to make something less concentrated
- 12. necessary for "fixing" nitrogen into plants
- 13. any mixture that has a uniform composition of substances (evenly mixed)
- 14. matter that has no definite shape or volume
- 15. a pure substance made of two ore more elements
- 16. matter with a definite shape that volume
- 22. a measure of how much space something takes up
- 24. a positively charged sub-atomic particle that tells you the identify of an element