Using Hess's law and equations 1-3 below, find ΔH° at 25°C for the oxidation of C₂H₅OH(l) .C₂H₅OH(l) + 3O₂(g) → 3H₂O(l) + 2CO₂(g)
1) C₂H₄(g) + 3O₂(g) → 2CO₂(g) + 2H₂O(l)
ΔH° = -1411 kJ
2) C(graphite) + 3H₂(g) + (1/2) O₂(g) → C₂H₅OH(l)
ΔH° = -278 kJ
3) C₂H₄(g) + H₂O(l) → C₂H₅OH(l)
ΔH° = -44 kJ

Question

Quizplus · Accepted Answer

The correct answer is A.The oxidation of C2H5OH(l) can be represented by the following equation:C2H5OH(l) + 3O2(g) → 3H2O(l) + 2CO2(g)The enthalpy change for this reaction can be calculated using Hess's law and equations 1-3:ΔH° = ΔH°1 + ΔH°2 + ΔH°3ΔH° = (-1411 kJ) + (-278 kJ) + (-44 kJ)ΔH° = -1733 kJTherefore, the enthalpy change for the oxidation of C2H5OH(l) is -1733 kJ.

Using Hess's Law and Equations 1-3 Below, Find ΔH° at 25°C