Question

What is the bond angle in chair conformers?

Answer 1

Cyclohexane has a non-planar structure which makes it almost free from ring strain. Cyclohexane has the ability to switch between boat, twist-boat, chair, and half-chair conformation. Stereoisomers that differ in the relative position of atoms within the molecule and by rotation about the sigma bond they can be interconverted are the conformational isomers. No breaking and remaking of covalent bonds are required in the interconversion of the conformational isomers.

Complete Step By Step Answer:
Chair conformation tells the angle between the carbon atoms in a ring appropriately, the position of the group on each carbon atom present can be known through chair conformation.
Chair conformation is a six-membered ring conformation with atoms 2,3,5 and 6 lying in the same plane and atom 1 lying above the plane and atom 4 lying below the plane. Because of a center of symmetry, chair conformation is achiral. Chair conformation is the stable conformation of cyclohexane. The C-C-C bonds are free from angle pressure, it is a staggered conformation and free of torsional stress.
The angle between the carbon atoms in cyclohexane is ${109.5^\circ }$ which makes it free of any bond strain.

Note:
The adjacent hydrogen atoms on all the closest carbon atoms are staggered hence there is a minimum force of repulsion in them, therefore, chair conformation is most stable. In boat conformations, the two hydrogen atoms are bonded to the first and fourth carbon atoms are near and repel each other. Boat conformation is less stable than a chair. Flagpole hydrogen is the hydrogen atom on the flagpole bonds.