Question

The minimum numbers of carbon atoms in ketones which will show chain isomerism will be:

• A. $7$
• B. $4$
• C. $6$
• D. $5$

Answer 1

The correct option is D $5$

There are minimum five carbon atoms in ketones which will show chain isomerism.

(i) $C{H}_3-\underset{O}{\underset{||}{C}}-C{H}_2-C{H}_2-C{H}_3$

(ii) $C{H}_3-\underset{O}{\underset{||}{C}}-\underset{C{H}_3}{\underset{|}{C}H}-C{H}_3$