If you start with 100 grams of a radionuclide, how much will you have after two half-lives have passed?

Question

Phoenix Kim

Chemistry

15 November, 10:26

If you start with 100 grams of a radionuclide, how much will you have after two half-lives have passed?

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Answers (2)

Know the Answer?

Stein · Answer 1

After first half-life you will have 100/2=50g. After second half-life you will have 50/2=25g.

Paula Peterson · Answer 2

25 grams.

A half life is the amount of time it takes for an isotope to decay half of itself.

So after one half life, there will be half of the original amount.

100/2=50

After another half life, there will be half of that amount.

50/2 = 25