Final answer:
The enthalpy change for the isomerization of maleic acid to fumaric acid is 23.2 kJ/mol, which was determined by subtracting the standard enthalpies of combustion of maleic acid from that of fumaric acid.
Step-by-step explanation:
The student posed a question relating to the standard enthalpy changes for the isomerization of maleic acid to fumaric acid. To calculate this, we use the given standard enthalpies of combustion for both compounds. First, we note that the enthalpy of combustion of fumaric acid is -1336.0 kJ/mol and that of maleic acid is -1359.2 kJ/mol.
To find the change in enthalpy (Delta H) for the isomerization reaction, we subtract the enthalpy of combustion of maleic acid from that of fumaric acid:
Delta H = Enthalpy of combustion (fumaric acid) - Enthalpy of combustion (maleic acid)
Delta H = (-1336.0 kJ/mol) - (-1359.2 kJ/mol)
Delta H = 23.2 kJ/mol
Therefore, the enthalpy change for the isomerization of maleic acid to fumaric acid is 23.2 kJ/mol, indicating an endothermic process.