Question

How can I compare the staggered conformer and eclipsed conformers for (ethane) `H_3C- CH_3` in Newman projections?

Answer 1

In the staggered conformation, the dihedral angle is 60 °. In the eclipsed conformation, the dihedral angle is 0 °.

Explanation:

Staggered Ethane

The dihedral angle is the angle between the front and rear bonds.

In the staggered version of ethane, the angle between the `"H"_A` and `"H"_B` bonds is 60 °.

Start by drawing a template for a staggered Newman Projection.

Then add `"H"` atoms to each of the bonds.

And you have your staggered Newman projection for ethane.

Eclipsed Ethane

In the eclipsed conformation, the angle behind the front and rear bonds is 0 °( I have off-set the rear bonds slightly so you can see them).

Then add `"H"` atoms to each of the bonds.

And you have your eclipsed Newman projection for ethane.