Calculate the enthalpy of the reaction below (∆Hrxn, in kJ) using the bond energies provided. N₂(g) + 3 H₂(g) → 2 NH₃(g)

Answer 1

If you have the bond energies, here is what you need to do.

1 x BE N2 + 3 x Be H2 - 6 BE N-H (BE stands for bond energy)

Note that ammonia has 3 N-H bonds, and there are 2 ammonia molecules, so there are 6 N-H bonds formed.