To calculate the enthalpy change H for the isomerization reaction of hexene from trans-hexene to cis-hexene, we can use the following equation:H = H products - H reactants In this case, the reactant is trans-hexene, and the product is cis-hexene. The standard enthalpy of formation values are given as -123 kJ/mol for trans-hexene and -130 kJ/mol for cis-hexene.H = -130 kJ/mol - -123 kJ/mol H = -130 + 123H = -7 kJ/molThe enthalpy change involved in the isomerization reaction of hexene from trans-hexene to cis-hexene is -7 kJ/mol.