Question

$ C{{H}_{3}}CH(OH)COOH $ shows:

• A. geometrical isomerism
• B. optical isomerism
• C. both [a] and [b]
• D. none of the above

Answer 1

Answer: (B)

(i) A compound shows geometrical isomerism if it has at least one carbon-carbon double bond and the two groups attached to the same carbon atom are different.
(ii) A compound shows optical isomerism if it has at least one asymmetric or chiral carbon atom and does not have plane of symmetry.
$H - \underset{\overset{|}{H}}{\overset{\underset{|}{H}}{C}} - \underset{\overset{|}{OH}}{\overset{\underset{|}{H}}{C}} * - \overset{\underset{||}{O}}{C} - OH $
$ \because $ The compound has one asymmetric carbon (marked $*$) atom.
$ \therefore $ It shows optical isomerism.
$ \because $ The compound does not have $C = C$.
$ \therefore $ It does not show geometrical isomerism.