What is the enthalpy change of a reaction at 45oC, if the enthalpy of reactant at 45oC and 25oC are 10 J and 6 J, and enthalpy of product at 45oC and 25oC are 15 J and 8 J, and the enthalpy change of reaction at 25oC is 10 J?

Correct Answer: 21 J
Heat of reaction = (10 – 6) + (15 – 8) + 10 = 21 J.