Consider the following reaction: $\large\frac{1}{2}$$H_2(g)+\large\frac{1}{2}$$Cl_2(g)\rightarrow HCl(g)$ $\Delta H=20KJ$.The activation energy for formation of HCl is 150KJ.Then activation energy for decomposition of HCl will be

Question

$\begin{array}{1 1}(a)\;150KJ\\(b)\;130KJ\\(c)\;20KJ\\(d)140KJ\end{array}$