The time required for completion of 93 . 75 % of a first order reaction is x minutes. The half life of it…
The time required for completion of of a first order reaction is minutes. The half life of it (in minutes) is
Solution
\(\begin{aligned} & t_{1 / 2}=\frac{0.0693}{k_1} \\ & \text {Also, } t_{93.75}=\frac{2.303}{k_1} \log \cdot \frac{100}{100-93.75} \\ & =\frac{2.303}{k_1} \log \cdot \frac{100}{6.25} \\ & =\frac{2.303}{k_1} \log 2^4 \\ & \frac{4 \times 2.303 \times \log 2}{k_1}=\frac{4 \times 0.693}{k_1}=4 t_{1 / 2}\end{aligned}\)
\(\begin{aligned}
& 4 t_{1 / 2}=\mathrm{x} \\
& t_{1 / 2}=\mathrm{x} / 4
\end{aligned}\)
So correct option is (3)
*
Asked in: JEE-TOPICTESTS-CHEMISTRY
Practice more CHEMICAL KINETICS questions on Aicharya