It is possible for the combustion of 1 mol of methane to have different values of $\Delta$H°, if the water produced in the combustion reaction is in the liquid or gaseous state at 25 °C.

Question

Quizplus · Accepted Answer

The enthalpy change ($\Delta$H°) depends on the state of the products; water in the liquid state releases more energy than in the gaseous state, leading to different $\Delta$H° values.

It Is Possible for the Combustion of 1 Mol of Methane