To calculate the equilibrium molar ratio of trans and cis isomers, you can use the relationship between Gibbs free energy change (ΔG°) and the equilibrium constant (K) given by: \(Δ
∘
=
−
ln
K\)
- Find \(
Δ
reaction
∘
=
Δ
trans
∘
−
Δ
cis\)\(
reaction
∘
=
41.549
kJ/mol
−
33.235
kJ/mol
=
8.314
kJ/mol
=
8314
J/mol
\)
2. Use ΔGreaction to calculate K (equilibrium constant):\(K=e−ΔG∘/RTK = e^{-\Delta G^\circ / RT}\)
\(−
Δ
∘
/
=
−
8314
/
2478.572
=
−
3.353
\)
- \(
=
−
3.353
≈
0.035\)
- This equilibrium constant K represents the ratio of trans to cis isomer. The ratio is approx 0.035:1. This indicates the cis isomer is significantly favored at equilibrium due to its lower free energy.