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The half life for radioactive decay of ....

The half life for radioactive decay of `.^(14)C` is 5730 years. An archaeological artifact containing wood had only `80%` of the `.^(14)C` found in a living tree. Estimat the age of the sample.

A

1485 years

B

1845 years

C

530 years

D

4767 years

Text Solution

Verified by Experts

The correct Answer is:
B

Radioactive decay follows first order kinetics.
Therefore,
Decau constant `(lambda) = (0.693)/(t_(1//2)) = (0.693)/(5730)`
Given `[R_(0)] = 100 :. [R] = 80`
and `t = (2.303)/(lambda) "log" ([R_(0)])/([R]) = (2.303)/((0.693)/(5730)) "log" (100)/(80)`
` = (2.303 xx 5730)/(0.693) xx 0.0969 = 1845` years
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