At constant pressure and 25°C,what is ΔH° for the following reaction
2C₂H₆(g) + 7O₂(g) → 4CO₂(g) + H₂O(l)
If the complete consumption of 38.2 g of C₂H₆ liberates 1981 kJ of heat energy?

Question

Quizplus · Accepted Answer

The molar mass of C₂H₆ is 30.07 g/mol. 38.2 g of C₂H₆ is 1.27 moles. The reaction liberates 1981 kJ for 1.27 moles, so for 2 moles (as per the balanced equation), ΔH° = (1981 kJ / 1.27 moles) * 2 moles = 3120 kJ.

At Constant Pressure and 25°C,what Is ΔH° for the Following