Across
- 5. a subatomic particle with no charge
- 7. composed of neutrons and protons
- 8. combining nuclei of two atoms to form a heavier atom
- 9. unstable atomic nucleus loses energy by radiation
- 11. The nuclei split into smaller fragments
- 12. number of protons and neutrons in the nucleus of an atom
- 16. measured in rems
- 18. smallest particle of an element
- 20. an electron resulting from the breaking apart of neutrons in an atom
- 21. identical to the Helium nucleus
Down
- 1. positively charged subatomic particle
- 2. amount of time it takes for half of a radioactive element to transform into something else
- 3. negatively charged subatomic particle
- 4. an atom or group of atoms that has a positive or negative charge
- 6. composed with protons and neutrons
- 10. number of protons in the nucleus
- 13. simplest form of matter that has a unique set of properties
- 14. rearrangement of DNA when hit by radiation
- 15. has no mass, can be stopped by several inches of lead (pure energy)
- 17. atoms of the same element with different numbers of neutrons
- 19. occurs when an unhappy nucleus ejects 2 protons and 2 neutrons