A substance `''A''` decomposes in solution following the first order kinetics. Flask `I` contains `1L` of `1 M` solution of `A` and falsk `II` contains `100 mL` of `0.6 M` solution. After `8 hr`, the concentration, of `A` in flask `I` becomes `0.25 M`. What will be the time for concentration of `A` in flask `II` to become `0.3 M` ?

Options

A. 0.4 h
B. 2.4 h
C. 4.0 h
D. Can’t be calculated since rate constant is not given

Answer

C

Explanation

The concentration of A remains 1/4th in 8 hours. Therefore, `1//(2)^(n), n=2`
and `E_(1//2)` is `8 = n xx t_(1//2), t_(1//2)=4`, In 4 hours 0.6 will become 0.3