QS Study

Differences between racemic mixture and meso compound

Racemic mixture

  • The equimolar mixture of two enantiomers is called racemic mixture e.g (+) and (-) lactic acid forms (±) – lactic acid as racemic mixture.
  • Racemic mixture is optically inactive due to external compensation.
  • It can be separated into two enantiomers which are optically active.
  • Racemic mixture may be formed from one or more than two asymmetric centres.

Meso compound

  • A meso compound has at least two identical asymmetric centers with a plane of symmetry e.g. meso tartaric acid.
  • Meso compound is optically inactive due to internal compensation.
  • Meso compound is a single compound which cannot be separated into optically active compound by resolution process.
  • Meso compounds should have at least two identical chiral centres.