How many half-lives have passed if the amount of Parent Isotope is 12.5%?

Question

Chemistry

Gingersnap

8 September, 05:37

How many half-lives have passed if the amount of Parent Isotope is 12.5%?

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Answers (1)

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Susan Hill · Answer 1

Three half lives.

Explanation:

Given dа ta:

Number of half lives passed = ?

Amount of parent isotope left = 12.5%

Solution:

At time zero = 100%

At 1st half life = 100%/2 = 50%

At second half life = 50%/2 = 25%

At third half life = 25%/2 = 12.5%

It means three half lives would passed.