Across
- 4. combining of atomic nuclei; releases large amounts of energy
- 7. made of an electron
- 9. a process by which unstable radioactive atoms lose energy through radiation
- 11. releases energy does not change the mass number or atomic number
- 13. made of energy; has no mass
- 14. splitting of a nucleus into fragments
Down
- 1. isotopes of atoms with unstable nuclei
- 2. time required for one-half of a radioisotope's nuclei to decay
- 3. increases the atomic number by 1
- 5. Reactions involving a change to an atom's nucleus
- 6. rays and particles emitted by radioactive material
- 8. decreases the mass number by 4 and the atomic number by 2
- 10. made of 2 protons and 2 neutrons
- 12. substances that spontaneously emit radiation