Easy INTEGER +4 / -1 PYQ · JEE Mains 2022

The rate constant for a first order reaction is given by the following equation:

$\ln k = 33.24 - {{2.0 \times {{10}^4}\,K} \over T}$

The activation energy for the reaction is given by ____________ kJ mol$-$1. (In nearest integer) (Given : R = 8.3 J K$-$1 mol$-$1)

Answer (integer) 166

Solution

$\ln \mathrm{k}=\ln \mathrm{A}-\frac{\mathrm{E}_{\mathrm{A}}}{\mathrm{RT}}$<br/><br/> Given: $\ln k=33.24-\frac{2.0 \times 10^4}{\mathrm{~T}}$<br/><br/> $$ \begin{aligned} &\therefore \text { on comparing } \frac{\mathrm{E}_{\mathrm{A}}}{\mathrm{R}}=2.0 \times 10^4 \\\\ &\therefore \mathrm{E}_{\mathrm{A}}=2.0 \times 10^4 \times \mathrm{R} \\\\ &\Rightarrow \mathrm{E}_{\mathrm{A}}=2.0 \times 10^4 \times 8.3 \mathrm{~J} \\\\ &\Rightarrow \mathrm{E}_{\mathrm{A}}=16.6 \times 10^4 \mathrm{~J}=166 \mathrm{~kJ} \end{aligned} $$

About this question

Subject: Chemistry · Chapter: Chemical Kinetics · Topic: Rate of Reaction

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