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Andre45 [30]
3 years ago
8

The half-life of Radium-226 is 1590 years. If a sample contains 100 mg, how many mg will remain after 4000 years?

Chemistry
1 answer:
guajiro [1.7K]3 years ago
4 0
We can calculate the amount left after 4000 years by using the half-life equation. It is expressed as:

A = Ao e^-kt

where A is the amount left at t years, Ao is the initial concentration, and k is a constant.

From the half-life data, we can calculate for k.

1/2(Ao) = Ao e^-k(1590)
k = 4.36 x 10^-4

A = 100 e^-<span> 4.36 x 10^-4(4000)
</span>A = 17.48 mg
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Answer:

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<em>Molarity of the solution:</em>

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<em>Mass percent:</em>

24.04g HCOOH / 1020g solution * 100

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