Across
- 5. What is the chemical symbol for gold?
- 6. The Study of living organisms
- 9. Smallest particle of an element
- 11. Which science explores the structure of matter and the changes it undergoes?
- 12. What is the name for the protective layer that shields the Earth from the sun's ultraviolet radiation?
- 13. Center of an atom
- 14. The study of rocks
- 15. Largest planet in our solar system
Down
- 1. The layer of Earth between the crust and the core
- 2. What gas do plants release during photosynthesis?
- 3. The third planet from the sun
- 4. Which gas makes up a majority of Earth's atmosphere?
- 7. The force that opposes motion between two surfaces
- 8. What do we call the study of stars, planets, and space?
- 10. Closest planet to the sun