Coal gasification can be represented by the equation: 2 C(s) + 2 H₂O(g) → CH₄(g) + CO₂(g) ΔH = ?
Use the following information to find ΔH for the reaction above.
CO(g) + H₂(g) → C(s) + H₂O(g) ΔH = -131 kJ
CO(g) + H₂O(g) → CO₂(g) + H₂(g) ΔH = -41 kJ
CO(g) + 3 H₂(g) → CH₄(g) + H₂O(g) ΔH = -206 kJ

Question

Quizplus · Accepted Answer

The correct answer is A because the enthalpy change for the reaction can be calculated using Hess's law:ΔH = ΔH1 + ΔH2 + ΔH3ΔH = (-131 kJ) + (-41 kJ) + (-206 kJ)ΔH = -378 kJHowever, the reaction is written in the reverse direction, so the enthalpy change must be multiplied by -1:ΔH = -(-378 kJ) = 378 kJ

Coal Gasification Can Be Represented by the Equation: 2 C(s)