Question

For a reaction $A_{2}+B_{2}$ ${\rightleftharpoons}$ $2AB$ the figure shows the path of the reaction in absence and presence of a catalyst. What will be the energy of activation for forward $\left(E_{f}\right)$ and backward $\left(E_{b}\right)$ reaction in presence of a catalyst and $\Delta H$ for the reaction? The dotted curve is the path of reaction in presence of a catalyst.

• A. $E_{f} =60 KJ /mol$, $E_{b}=70KJ /mol$, $\Delta H=20 KJ /mol$
• B. $E_{f} =20 KJ /mol$, $E_{b}=20KJ /mol$, $\Delta H=50 KJ /mol$
• C. $E_{f} =70 KJ /mol$, $E_{b}=20KJ /mol$, $\Delta H=10 KJ /mol$
• D. $E_{f} =10 KJ /mol$, $E_{b}=20KJ /mol$, $\Delta H=10 KJ /mol$

Answer 1

Answer: (D)

$E_{f}$ $=70-60=10 kJ/ mol$
$E_{b}$ $=70-50=20 kJ/ mol$
$\Delta H$ $=50-60$ $=-10 kJ /mol$