Lead-200 has a half-life of 21.5 hours. Starting with 20.0 mg of this isotope, how much would remain after 86 hours? a. 2.5 mg b. 1.25 mg c. 0.625 mg d. 0.37 mg e. 5.0 mg
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693 / half-life = 0.693 / 21.5 = 0.03228 Show more…
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