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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:

She lost 50.88 moles

Explanation:

Step 1: Data given

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Step 2: Calculate the initial number of moles

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p*V = n*R*T

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