The value of enthalpy change ΔH for the reaction
C2H5OH(1)+3O2(g)→2CO2(g)+3H2O(1) at 27∘C is−1366.5kJmol−1, The value of internal
energy change for the above reaction at this temperature will be:
-1364.0 kJ
C2H5OH(1)+3O2(g)→2CO2(g)+3H2O(1)Δng=2−3=−1ΔU=ΔH=ΔngRT=−1366.5−(1)×8.314103×300=−1366.5+0.8314×3=−1364kJ