Across
- 2. The form of energy we hear
- 4. Anything that has mass and takes up space
- 5. A substance made from two or more elements chemical
- 7. Basic unit of life
- 10. Energy source from the sun
Down
- 1. Smallest particle of an element
- 3. Neutral subatomic particle
- 6. The center of an atom
- 8. A substance that cannot be broken down into simpler substances by chemical means
- 9. The force that pulls objects towards the Earth