For questions 1-9, answer by typing the correct vocabulary term using the word bank below. 1) repulsive forces among protons in the nucleus

2) used to find the age of fossils and rock in Earth's layers

3)an atom that has a specific atomic number and atomic mass

4) the breakdown of an unstable radioactive isotope into a more stable element over time

5) atoms whose nuclei have the same number of protons but different numbers of neutrons

6) the amount of time it takes for half of a sample of a certain radioisotope to break down into a more stable element

7) attractive forces between protons and neutrons in the nucleus of an atom

8) when the attractive nuclear strong forces and repulsive electrical forces in an atom's nucleus are unbalanced

9) reactions of matter that involve changes to the nucleus and release a great amount of energy