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OleMash [197]
3 years ago
5

Radium-221 has a half-life of 30 sec. How long will it take for 96% of a sample to decay?

Chemistry
1 answer:
monitta3 years ago
3 0
We can calculate how long the decay by using the half-life equation. It is expressed as:

A = Ao e^-kt

<span>where A is the amount left at t years, Ao is the initial concentration, and k is a constant.
</span><span>From the half-life data, we can calculate for k.
</span>
1/2(Ao) = Ao e^-k(30)
<span>k = 0.023
</span>
0.04Ao = Ao e^0.023(t)
<span>t = 140 sec</span>
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