Question

The temperature dependence of rate constant (k) of a chemical reaction is written in terms of Arrhenius equation, $k = A.e ^{- E ^{*} / RT }$. Activation energy $\left( E ^{*}\right)$ of the reaction can be calculated by plotting

• A. log k vs $\frac{1}{T}$
• B. log k vs $\frac{1}{log \, T}$
• C. k vs T
• D. k vs $\frac{1}{log \, T}$

Answer 1

Answer: (A)

log k vs $\frac{1}{T}$

Answer 2

Arrhenius equation $k = Ae^{-E^{*}/RT} ln$ $k = ln A - \frac{E^{*}}{RT} \, \, \, \, \, \,$ (E* = energy of activation) or $log k = log A - \frac{E^{*}}{2.303 \, RT}$ Compare this equation with the straight line equation, i.e.\hspace20mm $y = mx + c$ where $'m'$ is slope and $c'$ is intercept Hence, $E$ is calculated with the help of following slope.