Why is a chair conformation of cyclohexane more stable?

This is to be compared with boat and twist-boat conformations whose substituents tend to eclipse each other to give unfavourable steric interactions. In a chair conformation, each face of the cyclohexane ring has three axial substituents, whose interaction is sterically unfavourable.

This response does not replace building a model from scratch and seeing three-dimensional trans-annular interactions.

The chair conformation of cyclohexane is more stable because it minimizes steric hindrance between substituents, resulting in lower energy levels. The staggered arrangement of bonds in the chair conformation allows for optimal bond angles and reduces strain compared to other conformations. Additionally, the chair conformation maximizes the number of axial substituents, which experience less steric hindrance than equatorial substituents, further contributing to its stability.