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A radioactive sample contains 2.2 mg pur...

A radioactive sample contains 2.2 mg pure `""_(6)^(11)C` which has half-life period of 1224 second Calculate.
(i) the number of atoms present initially.
(ii) the activity when `5mug` of the sample will be left.

Text Solution

Verified by Experts

(i) Number of atoms present initially
= `(6.023xx10^(23)xx2.2xx10^(-3))/11=1.2xx10^(20)`
(ii) Number of atoms present in `5mug` of the sample, N
= `(6.023xx10^(23)xx5xx10^(-6))/11=2.74xx10^(17)`
Activity of the sample = `lamdaN=0.693/T_(1//2)xxN`
= `0.693/1224xx2.74xx10^(17)`
= `1.55xx10^(14)` disintegrations/second.
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