Across
- 2. 46% of the Earth's weight is the answer
- 5. a hard object
- 6. it is the smallest unit of mater
- 7. the particles never stop moving
- 9. oxygen is usually the molecule
- 13. change when two chemicals react to others
- 14. it floats on water
- 15. the atomic number is 6
Down
- 1. the atomic number is 5
- 3. it is the least dense
- 4. it only has 1 atom
- 8. it is when a gas becomes a liquid
- 10. it is the most stable element
- 11. can take up any container
- 12. change when the size or shape changes
- 13. reaction involves breaking chemical bounds.