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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