Question

Why isn't it possible to isolate pure staggered ethane or pure eclipsed ethane at room temperature?

Answer 1

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Energetically there is difference of 3 kcal/mol. between the two conformation of ethane.Staggered is more stable than Eclipsed conformation only by 3 Kcal/mol.But this energy difference is not obtained at room temperature. At room temperature ethane molecules have enough energy to be in a constant state of rotation. Because of this rapid rotation, it is impossible to isolate any particular conformation.

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