Isotope-atoms of the same element that have the same number of protons but a different number of neutrons
Radioactive decay-the process by which an unstable atomic nucleus release energy and radioactive material
Alpha particle-a weak form of radioactive material that consists of two protons and two neutrons
Beta particle-radioactive material that consists of high energy electrons
Gamma rays– radioactive material in the form of very high frequency electromagnetic radiation
Half-life-the time it takes for half of the original nucleus of a radioactive substance to decay
Fission-occurs when a heavy nucleus splits into two lighter nuclei
Fusion-occurs when two light nuclei combine to form a heavier nucleus
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