Question

What is the activation energy for the reverse of this reaction?
$N_2{O}_4\left(g\right)⟶2N{O}_2\left(g\right)$
Data for the given reaction is: $\Delta H=+54$ $kJ$ and $E_f=+57.2$ $kJ$

• A. $-54$ $kJ$
• B. $+3.2$ $kJ$
• C. $+60.2$ $kJ$
• D. $+111.2$ $kJ$

Answer 1

The correct option is B $+3.2$ $kJ$

For endothermic reactions:

$E_b=E_f-\Delta H=57.2-54kL=3.2kL$