Across
- 5. a substance that can’t be broken down any further
- 8. the process of a gas turning into a liquid
- 10. negative ion or group of ions
Down
- 1. neutrally charged particle in the nucleus
- 2. positive ion or group of ions
- 3. number, number representing the number of protons and electrons
- 4. cloud, the area in an atom where electrons are found
- 6. red paper used in chemical identification
- 7. quantity of matter
- 9. center of the atom