Across
- 4. smallest paritcle of an element
- 5. Neutral subatomic particle in the nucleus
- 6. Contains protons and neutrons
- 8. fixed energy level surrounding the nucleus, where electrons occupy
- 10. Atoms of the same element with the **same number of protons** but **different numbers of neutrons**
Down
- 1. Protons + neutrons
- 2. Positive subatomic particle found in the nucleus
- 3. Proton number
- 7. Very light, negatively charged subatomic particle
- 9. A particle made of two or more atoms chemically bonded together