This is where a solution has equal amounts of both enantiomers. Enantiomers show optical isomerism and are two non-superimposable mirror images of each other. Enantiomers are formed due to chiral carbon atoms where each group attached to the carbon is different. These enantiomers can be L or D and within a racemic mixture, it contains 50% of each enantiomer. To identify a racemic mixture, experimentally you could use plane polarised light. Enantiomers rotate plane polarised light in opposite directions, so in a racemic mixture there is no overall rotation as the two enantiomers cancel each other out.