For a reaction taking place in three steps at same temperature, overall rate constant K =(K_1 K_2)/(K_3). If Ea_1, Ea_2 and Ea_3 are 40, 50 and 60 kJ…

For a reaction taking place in three steps at same temperature, overall rate constant $\displaystyle \mathrm{K}=\frac{\mathrm{K}_1 \mathrm{~K}_2}{\mathrm{~K}_3}$. If $\displaystyle \mathrm{Ea}_1, \mathrm{Ea}_2$ and $\displaystyle \mathrm{Ea}_3$ are $\displaystyle 40$, $\displaystyle 50$ and $\displaystyle 60 \mathrm{~kJ} / \mathrm{mol}$ respectively, the overall Ea is $\displaystyle \_\_\_\_$ $\displaystyle \mathrm{kJ} / \mathrm{mol}$.