AP BIOLOGY

Detailed explanation-1: -This chair conformation is the lowest energy conformation for cyclohexane with an overall ring strain of 0 kJ/mol. In this conformation, the carbon-carbon ring bonds are able to assume bonding angles of  111o which is very near the optimal tetrahedral 109.5o so angle strain has been eliminated.

Detailed explanation-2: -The energies of the boat and half-chair states are 6.6 kcal mol−1 (28 kJ mol−1) and 10.8 kcal mol−1 (45 kJ mol−1) higher than that of the chair. The conformations involve following order of stability: chair form > twist boat form > boat form > half-chair form.

Detailed explanation-3: -Ring flipping Cyclohexane rapidly interconverts between two stable chair conformations because of the ease of bond rotation. The energy barrier is about 45 kJ/mol, and the thermal energies of the molecules at room temperature are great enough to cause about 1 million interconversions to occur per second.

Detailed explanation-4: -Examples of common conformations of cyclohexane include the boat, the twist-boat, the chair, and the half-chair conformations, which are named based on the shape that the cyclohexane molecule assumes in them.