Question

d-tartaric acid and l-tartaric acid are:

• A. enantiomers
• B. tautomers
• C. diastereoisomers
• D. structural isomers

Answer 1

The correct option is A enantiomers

(S)-(d)-lactic acid (left) and (R)-(l)-lactic acid (right) are non-superimposable mirror images of each other.
An enantiomer is one of two stereo isomers that are mirror image of each other that are non-superimposable (not identical), much as one's left and right hands are the same except for being reversed along one axis (the hands cannot be made to appear identical simply by reorientation). Organic compounds that contain a chiral carbon usually have two non-superimposable structures. These two structures are mirror images of each other and are, thus, commonly called enantiomorphs.