The decomposition of dinitrogen pentaoxide has and activation energy of 102 kj/mol and delta H degree rsn = + 55 kj/mol. What is the activation energy for the reverse reaction?
a. 27 kj/mol
b. 47 kj/mol
c. 55 kj/mol
d. 102 kj/mol
e. more information is needed, since this is a Hess's law calculation