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The half life of a radioactive isotope i...

The half life of a radioactive isotope is three hours. If the initial mass of the isotope was 300 g, the mass which remained undecayed in 18 hours would be :

A

2.34g

B

1.17 g

C

9.36 g

D

4.68 g

Text Solution

Verified by Experts

The correct Answer is:
D
Amount left after n half lives `=(N_(0))/(2^(n))=(300)/(2^(6))`
`=(300)/(64)=4.68g`
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