For a first order reaction, $A \rightarrow P$, the temperature $(T)$ dependent rate constant $(k)$ was found…

For a first order reaction, $A \rightarrow P$, the temperature $(T)$ dependent rate constant $(k)$ was found to follow the equation, $\log k=-(2000) / T+6.0$ The pre-exponential factor $A$ and the activation energy $\left(E_a\right)$, respectively, are
  1. $1.0 \times 10^6 \mathrm{~s}^{-1}$ and $9.2 \mathrm{~kJ} \mathrm{~mol}^{-1}$
  2. $6.0 \mathrm{~s}^{-1}$ and $16.6 \mathrm{~kJ} \mathrm{~mol}^{-1}$
  3. $1.0 \times 10^6 \mathrm{~s}^{-1}$ and $16.6 \mathrm{~kJ} \mathrm{~mol}^{-1}$
  4. $1.0 \times 10^6 \mathrm{~s}^{-1}$ and $38.3 \mathrm{~kJ} \mathrm{~mol}^{-1}$

Solution

Comparing the slope and intercept of the given equation with the following Arrhenius equation : $ \log k=-\frac{E_a}{2303 R T}+\log A $ Hence, $\log A=6$ i.e. $A=10^6 \mathrm{~s}^{-1}$. Comparing slope gives $E_a=38.3 \mathrm{~kJ} / \mathrm{mol}$

Asked in: JEE Advanced 2009 (Paper 2)

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