Catalyst A reduces the activation energy for a reaction by $10 \mathrm{~kJ} \mathrm{~mol}^{-1}$ at 300 K . The ratio of rate constants, $\frac{{ }^{\mathrm{k}} \mathrm{T}, \text { Catalysed }}{{ }^{\mathrm{k}} \mathrm{T}, \text { Uncatalysed }}$ is $\mathrm{e}^{\mathrm{x}}$. The value of x is $\_\_\_\_$ . [nearest integer] [Assume theat the pre-exponential factor is same in both the cases. Given $\left.\mathrm{R}=8.31 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}\right]$