Chemistry - Chemical Kinetics Question with Solution | TestHub

Initial concentration ${\mathrm{a}}_0=\mathrm{a}$ (let) Final concentration $a_t=\frac{a}{8}$ $1^{\text{st }}$ order reaction $$\begin{array}{rl}& \mathrm{k}=\frac{2.303}{\mathrm{t}}\log \frac{{\mathrm{a}}_0}{{\mathrm{a}}_{\mathrm{t}}}=\frac{2.303}{23.03}\log \frac{\mathrm{a}}{\mathrm{a}/8}\\ & \mathrm{k}=\frac{1}{10}\log 8=\frac{3}{10}\log 2=0.3\log 2\end{array}$$ Half -life ${\mathrm{t}}_{1/2}=\frac{2.303\log 2}{\mathrm{k}}$ $$\begin{array}{rl}& =\frac{2.303\times \log }{0.3\log 2}\\ & =7.7\min \end{array}$$