Question

The rate constant, the activation energy and the Arrhenius parameter (A) of a chemical reaction at ${25}^{\circ }C$ are $3.0\times {10}^{-22}{s}^{-1},$ 104.4 kJ $mo{l}^{-1}$ $6.0\times {10}^{14}{s}^{-1}$and respectively. The value of the rate constant at $T\to \infty$ is:

• A. $2.0\times {10}^{18}{s}^{-1}$
• B. $6.0\times {10}^{14}{s}^{-1}$
• C. Infinity
• D. $3.6\times {10}^{30}{s}^{-1}$

Answer 1

The correct option is B $6.0\times {10}^{14}{s}^{-1}$

Arrhenius equation

$\Rightarrow K={Ae}^{-Ea/RT}$

As $T\to \infty$,

$RT\to \infty$

$\frac{-Ea}{RT}\to 0$

$e^{-Ea/RT}\to 1$

Hence $K\to A$ as $T\to \infty$

$\therefore$Value of K as $T\to \infty$ = $6.0\times {10}^{14}{S}^{-1}$