Question

The rate of the first order reaction is $0.69\times {10}^{-2}mol{L}^{-1}{min}^{-1}$ and the initial concentration is $0.2mol{L}^{-1}$. The half life period is:

• A. $1205s$
• B. $330$
• C. $600s$
• D. $1s$

Answer 1

The correct option is A $1205s$

Half-life for first order reaction,

$t_{1/2}=\frac{0.693}{K}=\frac{0.693}{r}\times \left[A_o\right]\because r=K\left[A_o\right]$

$\therefore t_{1/2}=\frac{0.693\times 60\times 0.2}{0.69\times {10}^{-2}}=1200s\left(approx\right)$