Across
- 4. total number of neutron and protons.
- 6. a radioactive isotope.
- 8. a number of chemical activity elements.
- 9. same but different.
- 10. has a positive charge.
- 12. has high energy or speed.
Down
- 1. the amount of time it take to decay.
- 2. combining.
- 3. bumps into a larger atom and splits.
- 5. emitting radiation.
- 7. 26th letter in the alphabet.
- 8. particles tightly bounded together.
- 11. charge of zero.