QuestionStereochemistry / Newman projections
Two compounds [X] and [Y] are given below:

The relationship between [X] and [Y] is:
- (a) Identical
- (b) Diastereomers
- (c) Enantiomers
- (d) Constitutional isomers
Answer: (c) Enantiomers
Both are butan-2-ol. On the stereocentre, H and the ethyl carbon keep their places while OH and CH₃ swap between [X] and [Y]. One swap = inverted configuration → enantiomers → (c).