Calculate the standard enthalpy of formation of acetylene (in kJ·mol–1).
2C₂H₂(g) + 5O₂(g) → 4CO₂(g) + 2H₂O(l) ∆H˚ = –2243.6 kJ
C(s) + O₂(g) → CO₂(g) ∆H˚ = –393.5 kJ
H₂(g) + 1/2 O₂(g) → H₂O(l) ∆H˚ = –285.8 kJ

Question

Calculate the standard enthalpy of formation of acetylene  (in kJ·mol–1).
2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O(l) ∆H˚ = –2243.6 kJ
C(s) +  O2(g) → CO2(g) ∆H˚ = –393.5 kJ
H2(g) + 1/2 O2(g) → H2O(l) ∆H˚ = –285.8 kJ

Accepted Answer

Correct answer: A.

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