Practice Stereoisomer Relationships
Molecule A
Molecule B
Common Questions
What is the difference between enantiomers and diastereomers?
Enantiomers are non-superimposable mirror images — every stereocenter is inverted. Diastereomers are stereoisomers that are not mirror images — at least one stereocenter is the same and at least one is different.
How do you tell if two molecules are identical?
Two molecules are identical if you can superimpose them by rotation and translation. If every stereocenter has the same R/S configuration in both structures, they are the same compound.
What are structural isomers vs. stereoisomers?
Structural (constitutional) isomers have the same molecular formula but different atom connectivity. Stereoisomers have the same connectivity but differ in the 3D arrangement of atoms.
Do enantiomers have the same physical properties?
Enantiomers have identical physical properties (melting point, boiling point, solubility) except for the direction they rotate plane-polarized light and how they interact with other chiral molecules.