Final answer:
The ΔH for the coal gasification reaction is -566.0 kJ.
Step-by-step explanation:
We can use the given information and Hess's law to find the ΔH for the coal gasification reaction. First, we need to write two equations that can be added together to give the desired equation:
2 CO(g) → 2 C(s) + O₂(g) ΔH = +221.0 kJ
C(s) + O₂(g) → CO₂(g) ΔH = -393.5 kJ
By reversing the first equation and multiplying the second equation by 2, we get:
2 C(s) + 2 O₂(g) → 2 CO₂(g) ΔH = -787.0 kJ
Adding these two equations together gives us the desired equation:
2 C(s) + 2 H₂O(g) → CH₄(g) + CO₂(g) ΔH = -566.0 kJ
Therefore, the ΔH for the coal gasification reaction is -566.0 kJ.