Question

The number of possible optical isomers of lactic acid are:

• A. 2
• B. 4
• C. many
• D. none of these

Answer 1

Answer: (A)

2

Answer 2

Lactic has only one chiral carbon atom, hence, it has only 2 isomers possible, which are d- and $l$ -lactic acid. $H-\underset{COOH}{\overset{C{{H}_{3}}}{\mathop{\underset{|}{\overset{|}{\mathop{{{C}^{*}}}}}\,}}}\,-OH,\underset{d\text{-}\,\text{and}\,l\text{-lactic}\,\text{acid}}{\mathop{HO-\underset{COOH}{\overset{C{{H}_{3}}}{\mathop{\underset{|}{\overset{|}{\mathop{{{C}^{*}}}}}\,}}}\,-H}}\,$