AP Chemistry· difficulty 3/5
For CH₄(g) + 2 O₂(g) → CO₂(g) + 2 H₂O(l), use ΔH_f° values.
What is ΔH for the combustion of methane?
−890.3 kJ
−604.5 kJ
+890.3 kJ
−1184 kJ
Explanation
ΔH = [(-393.5) + 2(-285.8)] − [(-74.8) + 0] = (-393.5 − 571.6) + 74.8 = -965.1 + 74.8 = -890.3 kJ.
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