Answer
See the answer below.
Work Step by Step
For this reaction 2 H-H bonds and 1 O=O are broken, 4 O-H bonds are formed.
Since the energies are for bond dissociation, 4 times the bond dissociation energy (b.d.e) for the O-H bond must be subtracted from the sum of the b.d.e. for O=O with 2 times the b.d.e. for H-H. The result will be an estimate for the enthalpy of the reaction.
