question_answer 1)

  Draw Newman and Sawhorse projections for the eclipsed and staggered conformations of ethane. Which of these conformations is more stable and why?

Answer:

  The staggered conformation is most stable because the hydrogens and bonding pairs of electrons are at maximum distance. This causes minimum repulsion. The eclipsed conformation is least stable and the other intermediate conformation (Gauche or skew form) lies between these two in stability.