D-tartaric acid and L-tartaric acid are two chiral molecules of tartaric acid that are enantiomers of each other. Enantiomers are non-superimposable mirror images of each other, meaning they have the same molecular formula and connectivity but differ in the spatial arrangement of their atoms. In the case of tartaric acid, the two enantiomers have different configurations at their chiral centers carbon atoms with four different substituents .The relationship between D-tartaric acid and L-tartaric acid can be understood using the Cahn-Ingold-Prelog CIP priority rules and the D/L nomenclature system. D-tartaric acid has the hydroxyl group on the right side of the chiral center when drawn in the Fischer projection, while L-tartaric acid has the hydroxyl group on the left side. It is important to note that the D/L system is different from the R/S system, which is more commonly used in modern stereochemistry.When it comes to their effect on plane-polarized light, enantiomers have the unique property of rotating the plane of polarized light in opposite directions. D-tartaric acid rotates the plane of polarized light to the right dextrorotatory , while L-tartaric acid rotates it to the left levorotatory . The specific rotation values for each enantiomer are equal in magnitude but opposite in sign. This optical activity is a characteristic property of chiral molecules and can be used to distinguish between enantiomers.In summary, D-tartaric acid and L-tartaric acid are enantiomers of tartaric acid with different spatial arrangements of their atoms, and they rotate plane-polarized light in opposite directions.