Take butane as existing only as one anti conformer (energy 0) and two equivalent gauche conformers (each 3.8 kJ/mol above anti). Use $R = 8.314 J K^{- 1} mo l^{- 1}$ and Boltzmann statistics at 298 K. The percentage of molecules in gauche conformers is closest to

A17.7%
B43.1%
C69.9%
D30.1%

Answer: D

Weights: anti = 1, each gauche =

e^{- 3800/ (8.314 \times 298)} = e^{- 1.534} = 0.2157

, two of them give 0.4314. Gauche fraction = 0.4314/(1 + 0.4314) = 30.1%. Forgetting that there are two gauche forms gives 17.7%, and not normalising gives 43.1%.

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Take butane as existing only as one anti conformer (energy 0) and two equivalent gauche conformers (each 3.8 kJ/mol above anti). Use R=8.314 JK−1mol−1 and Boltzmann statistics at 298 K. The percentage of molecules in gauche conformers is closest to

Answer: D

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Take butane as existing only as one anti conformer (energy 0) and two equivalent gauche conformers (each 3.8 kJ/mol above anti). Use $R = 8.314 J K^{- 1} mo l^{- 1}$ and Boltzmann statistics at 298 K. The percentage of molecules in gauche conformers is closest to