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QOTD. How do we measure the stability of an atom?. Half Life. Mr. Dunnum. Radioactivity. An unstable atomic nucleus emits a form of radiation (alpha, beta, or gamma) to become stable. In other words, the nucleus decays into a different atom. Radioactivity. Alpha Particle – Helium nucleus
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QOTD • How do we measure the stability of an atom?
Half Life Mr. Dunnum
Radioactivity • An unstable atomic nucleus emits a form of radiation (alpha, beta, or gamma) to become stable. • In other words, the nucleus decays into a different atom.
Radioactivity • Alpha Particle – Helium nucleus • Beta Particle – electron • Gamma Ray – high-energy photon
Half-Life • Amount of time it takes for one half of a sample of radioactive atoms to decay
Half-Life Calculation #1 • You have 400 mg of a radioisotope with a half-life of 5 minutes. How much will be left after 30 minutes? • Half-Life Calculation #1 • 6.25 mg
Half-Life Calculation # 2 • In a sample of 8160g of Co-60, how much of the sample is left after 5 half-lives have passed? • Half-Life Calculation #2 • 255g