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lorasvet [3.4K]
4 years ago
7

Francium decays with a half-life of 22 minutes. If we start out with 639 mg of francium,how much would remain after 2.7 hours?

Physics
1 answer:
Vinil7 [7]4 years ago
6 0

Answer:

3.87 or 3.9 mg

Explanation:

2.7h * 60mins = 162mins

number of 1/2 lives = 162/22= 7.364

amount remaining = 639(1/2)^7.364 = 3.8796

answer = 3.87 or 3.9

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