question_answer

Which one among the following contains a phenolic \[-OH\] group?

A)  Oxalic acid         

B)  Formic acid

C)   Picric acid          

D)   Citric acid

Correct Answer: C

Solution :

Key Idea: Draw all the structures to find which of them has phenolic \[-OH\] group. [a] Oxalic acid\[\begin{align}   & COOH \\  & | \\  & COOH \\ \end{align}\] [b] Formic acid\[HCOOH\] [d] Critic acid \[HOOC-C{{H}_{2}}-\underset{\begin{smallmatrix}  | \\  COOH \end{smallmatrix}}{\overset{\begin{smallmatrix}  OH \\  | \end{smallmatrix}}{\mathop{C}}}\,-C{{H}_{2}}-COOH\] \[\therefore \]Picric acid has phenolic \[-OH\] group.