Question

Which of the following pairs are related as position isomers?

• A. $C{H}_2\left(OH\right)C{H}_{2}COOHandC{H}_3-CH\left(OH\right)COOH$
• B. $C_2{H}_{5}OHandC{H}_{3}OC{H}_3$
• C. $(C_2{H}_5{)}_{2}COandC{H}_{3}CH=C(OH)C{H}_{2}C{H}_3$
• D. All the above

Answer 1

The correct option is A $C{H}_2\left(OH\right)C{H}_{2}COOHandC{H}_3-CH\left(OH\right)COOH$

Structural isomers with a difference in the position of multiple bond/functional group/alkyl substituent on the same carbon skeleton (parent chain) is called position isomers.
In (a), $OH$ is positioned at different carbon atoms. Hence, they are position isomers.

In (b), we have alcohol and ether functional groups. Hence, they are functional isomers.
In (c), we have keto and enol forms. So, they are tautomers.