Discuss the optical isomerism of lactic acid.

Explanation

(i) The optical isomerism of Lactic acid.
Lactic acid is a-hydroxypropanoic acid `[CH_3 *CH(OH) COOH].`
It has one chiral (asymmetric centre marked by *)
It exists in d-, l- and racemic (dl) forms.
The structures of its enantiomers are:
(ii) No, a compound of the type abC =Cab does not show geometrical isomerism.
To show geometrical isomerism, there must be a doubly bonded carbon atom and two atoms or groups attached to the each double bonded carbon atom should be different.
Alkenes with general formula abC=Cab, abC=Ccd, abC=Cax show geometrical isomerism.
While compounds like aaC=Cab or aaC=Cbb cannot show geometrical isomerism.