Editing Racemic mixture (section)

==History==
The first known racemic mixture was [[racemic acid]], which [[Louis Pasteur]] found to be a mixture of the two enantiomeric [[isomer]]s of [[tartaric acid]]. He manually separated the crystals of a mixture, starting from an aqueous solution of the sodium ammonium salt of racemate tartaric acid.  Pasteur benefited from the fact that ammonium tartrate salt gives enantiomeric crystals with distinct crystal forms (at 77&nbsp;°F). Reasoning from the macroscopic scale down to the molecular, he reckoned that the molecules had to have non-superimposable mirror images.<ref>{{cite book |doi=10.1016/B978-0-444-51675-6.50018-9 |chapter=Substances |title=Philosophy of Chemistry |year=2012 |last1=Brakel |first1=Jaap van |pages=191–229 |isbn=978-0-444-51675-6 }}</ref>
A sample with only a single enantiomer is an ''enantiomerically pure'' or ''enantiopure'' compound.<ref>{{cite book|last=Moss|first=Gerry P.|title=Basic terminology of stereochemistry (IUPAC Recommendations 1996)|year=1996|publisher=Blackwell Scientific Publications|location=Department of Chemistry, Queen Mary University of London|pages=8, 11|url=http://www.chem.qmul.ac.uk/iupac/stereo/}}</ref>