Question

Which is the most unstable conformation of cyclohexane why?

Answer 1

Answer:

Half chair form.

Explanation:

It is the conformer of cyclohexane having the highest enegry in the energy profile diagram of cyclohexane. All kind of strains are present in this particular conformer and more over, in this conformer, there a 5 carbon atoms in the same plane, thus causing a strained structure similar to planar cyclohexane.

But the half chair form is the most stable conformer or cyclohexene, since it has a double bond and double bond prefers planarity in the molecule, which will be easily provided by the half chair form of cyclohexene and not by the other conformers.

Answer 2

Half chair form is the most unstable conformation of cyclohexane.

Explanation:

• Half chair form is the conformer of cyclohexane which is having the highest energy

• This energy is shown in the energy profile diagram of cyclohexane.

• The stable conformation of cyclohexane is the chair form.

• In chair form Here the C-C-C bond is nearly 109.5 degrees.

• The Chair form is free from angle strain. This form is a staggered conformation which is free from torsional strain.