Chemistry - Chemical Kinetics Question with Solution | TestHub

For a first order reaction, the rate constant $k$ is related to the half life period $t_{1/2}$ by the formula:

$k=\frac{0.693}{t_{1/2}}$

Given $t_{1/2}=1386\text{ s}$, substituting this value:

$k=\frac{0.693}{1386}$

$k=\frac{693\times 10^{-3}}{2\times 693}$

$k=0.5\times 10^{-3}{\text{ s}}^{-1}$

Answer: $0.5\times 10^{-3}\times s^{-1}$