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A 0.50g sample of rock was found to have...

A 0.50g sample of rock was found to have `2.5 xx 10^(-6)` mol of `._(19)^(40)K (t_(1//2)=1.3 xx 10^(9) "yr")` and `7.5 xx 10^(-6)` mol of `._(20)^(40)Ca` . How old is the rock?

A

`6.5 xx 10^(8)` yr

B

`1.3 xx 10^(9)` yr

C

`2.6 xx 10^(9)` yr

D

`5.2 xx 10^(9)` yr

Text Solution

Verified by Experts

The correct Answer is:
C
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