We’re being asked to calculate AG° (in kJ/mol) for the following reaction at 1 atm and 25°C:

C_{2}H_{6}(g) + O_{2}(g) → CO_{2}(g) + H_{2}O(l)

We can use the following equation to solve for ** ΔG˚_{rxn}**:

$\overline{){\mathbf{\Delta G}}{{\mathbf{\xb0}}}_{{\mathbf{rxn}}}{\mathbf{=}}{\mathbf{\Delta H}}{{\mathbf{\xb0}}}_{{\mathbf{rxn}}}{\mathbf{-}}{\mathbf{T\Delta S}}{{\mathbf{\xb0}}}_{{\mathbf{rxn}}}}$

For this problem, we need to do the following steps:

**Step 1:**** **Calculate ΔH˚_{rxn}.

**Step 2:**** **Calculate ΔS˚_{rxn}.

* Step 3:* Use ΔH˚

Calculate AG° (in kJ/mol) for the following reaction at 1 atm and 25°C

C_{2}H_{6} (g) + O_{2} (g) → CO_{2} (g) H_{2}O (l)

ΔH_{f}° C2H6 (g) = -84.7 kJ/mol; S° C_{2}H_{6} (g) = 229.5 J/K • mol;

ΔH_{f}° CO_{2 }(g) = 393.5 kJ/mol; S° CO_{2} (g) = 213.6 J/K • mol;

ΔH_{f}° H_{2}O (l) = -285.8 kJ/mol; S° H_{2}O (l) = 69.9 J/K • mol

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