Name:
Class:
Radioactivity
Across
2. a nuclei that has a high proton-to-neutron ratio
5. decay where the atomic and mass number remain the same
7. francium will alpha decay into ___
10. nuclear decay is also known as ___
12. radium decays into ___ after emitting alpha particles
Down
1. nuclear ____ reaction where a nucleus reacts to form an even more massive nucleus
3. elements with atomic number 83 or higher
4. atoms with a high energy level are said to be ___ and prone to decay
6. means to break down or disintegrate
8. gamma rays are emitted in the form of ___
9. decay that emits an electron
11. an atom of helium ejected from a bigger nucleus
Class No.: