To calculate the enthalpy change H for the isomerization of butene-1 to butene-2, we can use the following equation:H = Hf products - Hf reactants In this case, the reactant is butene-1 and the product is butene-2. Hydrogen gas is not involved in the isomerization process, so we don't need its enthalpy of formation.Let's denote the enthalpy of formation of butene-1 as Hf butene-1 and the enthalpy of formation of butene-2 as Hf butene-2 .Now, we can plug the values into the equation:H = Hf butene-2 - Hf butene-1 Please provide the enthalpies of formation for butene-1 and butene-2 to calculate the enthalpy change for the isomerization.