The O-H bond energy is 464 kJ/mol and the HI bond energy is 291 kJ/mol. Remembering that breaking any bond is an endothermic process and making any bond is exothermic, what is the net enthalpy change involved in the reaction between HI and H2O? Is this reaction endothermic or exothermic?

Explanation:

The reaction equation will be as follows.

In this reaction, breakage of hydrogen and chlorine bond takes place whereas the formation of O-H bond takes place.

Therefore, enthalpy of the reaction will be calculated as follows.

                        =

                       = 432 kJ/mol - 464 kJ/mol

                       = -32 kJ/mol

Negative sign indicates that heat is liberating.

Thus, we can conclude that the given reaction is exothermic in nature and net enthalpy change is 32 kJ/mol.