Question

What is a staggered conformer in a Newman projection?

Answer 1

Conformers are the compounds having the same molecular formula but different arrangement of atoms in space. They are examples of stereoisomers, which means that atoms exist in space. Conformers have different spatial arrangements of atoms that can be changed into another. They consist of the C – C bond having free rotation.

Complete answer:
Different spatial arrangements of atoms in space are possible due to confirmation, which is the property of atoms to arrange in different positions that have the same molecular formula. They are known as conformers or rotamers as they consist of the rotation of atoms around the C – C bond. This rotation is a bit hindered due to a small energy barrier caused by weak repulsive interaction between adjacent atoms. One type of conformation is Newman projection.
Newman projection consists of 3 types of conformers, staggered, eclipsed and skew. The staggered conformation of Newman projection consists of a front and a back carbon denoted as $\bullet$ and ${\mathrm O}$respectively. The staggered conformers consist of the atoms at particular distance, where the atoms attached with the backside carbon bisects the angles formed from the bonds of the atoms of the front carbon. The representation of a staggered Newman projection for instance of ethane $C{{H}_{3}}-C{{H}_{3}}$is:

Hence, a staggered conformer in a Newman projection shows the bonds and atoms situated at a distance where the bonds at the back bisect the bonds of the front atoms.

Note:
Apart from staggered, Newman projection also has eclipsed and skew conformers as

respectively. The order of their stability is staggered > skew > eclipsed. This is due to the fact that the bonds are at maximum distance in staggered that creates minimum repulsion between the atoms making it the most stable. In skew they are a bit closer than staggered while in eclipse the bonds are the closest.