Question

At ${25}^{o}C$, the values of rate constant, activation energy and Arrhenius constant of a reaction are $3\times {10}^{-4}{sec}^{-1}$, $129kJ/mol$ and $2\times {10}^{15}{sec}^{-1}$ respectively.
The value of rate constant (in $se{c}^{-1}$) as $T\to \infty$ is:

• A. $0$
• B. $2\times {10}^{15}$
• C. $3\times {10}^{-4}$
• D. $6\times {10}^{11}$

Answer 1

Answer: (B)

$2\times {10}^{15}$

$k=A{e}^{-\frac{E_a}{RT}}$

${lim}_{T\to \infty }\left(k\right)=A{lim}_{T\to \infty }\left(e^{-\frac{E_a}{RT}}\right){lim}_{T\to \infty }\left(k\right)=A=2\times {10}^{15}{s}^{-1}$