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The formula for the half-life can be expressed as
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- Learning Goal: Radioactive decay - Half-life N 1,000,000 500,000 250,000 125,000 62,500 Number of nuclides, N x 10³ 1000 750 500 250 125 0 Time 0 the 2012 3h2 4112 5h2 612 7h2 8h2 9412 10₁2 31,250 15,625 he 2h 3h 4h 5h 6h 7he 8he 9h 10h Time in multiples of f 7,813 3,906 1,953 977 A radioactive sample's half-life is 30.2 years. 1 year = 365 days, 1 day = 24 hours, 1 hour = 60 min, 1 min = 60 sarrow_forwardThe radioactive gas krypton-85, produced by nuclear power plants as well as volcanoes, is present in trace amounts in earth’s atmosphere. Its half-life is 10.8 years. Suppose a volcano released 250 g of krypton-85 in an eruption. How much would remain after (a) 10.8 years, (b) 15 years, and (c) 50 years? Round to the nearest tenth of a gram.arrow_forwardThere was a sample of 500 milligrams of a radioactive substance to start a study. Since then, the sample has decayed by 2.6% each year. Let & be the number of years since the start of the study. Let y be the mass of the sample in milligrams. Write an exponential function showing the relationship between y and t.arrow_forward
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