Following are four Newman projection formulas for tartaric acid. (a) Which represent the

Key concepts

Newman projection

A Newman projection is a way of representing the conformation of a molecule by looking at it along a specific bond axis. It is a two-dimensional representation that shows the relative orientation of the atoms in a molecule.

Enantiomers

Enantiomers are defined as the molecules that are mirror images to each other but are non-superimposable. In other words, when you draw Fischer projection of both the molecule, then they have exactly opposite configurations at each and every chiral carbon atom.

Diastereomers

Diastereomers are defined as the molecules that have the same molecular formula but are not mirror images to each other. In other words, when you draw Fischer projection of both the molecules, then they have chiral centers with different with at least one chiral center  and .

Identical molecules

Identical molecules are defined as the molecules that have the same configurations at each and every chiral carbon atom.

Meso compounds

A meso compound is a compound that contains a plane of symmetry (a center of symmetry or a mirror plane) in its molecular structure. This means that the compound is superimposable on its own mirror image, and therefore, it has two or more stereoisomers that are identical.

Meso compounds are often found in compounds with multiple functional groups and are also called diastereomers. They are different from enantiomers, which are stereoisomers that are mirror images of each other but are not superimposable.

Step 1 of 2

Here we are given Newman projections of tartaric acid, we have to find which represents the same compound, enantiomers, diastereomers and meso compounds.

Now, in this case, we are given Newman projections of each molecule. we first need to draw Fischer projection of each of those molecule and then assign the  or  configuration to each chiral carbon atom.