Question

What are the functional groups in the following compounds?
A.Aniline
B.\[\beta - naphthol\]
C.\[m - nitro{\text{ }}aniline\]
D.\[oxalic{\text{ }}acid\]

Answer 1

Hint: In the given question different compounds are given. To find the answers to the following compounds one can either derive the answer from the nomenclature or another way is to draw the structure of the following compounds.

Complete answer:
Let’s explore the given options one by one
The first compound given to us is aniline. The IUPAC name of aniline is \[phenylamine\]. It is very much evident from the name that aniline consists of a phenyl group attached to an amino group. While naming an amine the root name is based on the longest chain or the parent compound followed by the suffix –amine. So the functional group of the compound aniline is an amine or amino group attached to a benzene ring or phenyl group.
For the second compound \[\beta - naphthol\] there is a naphthol group attached to a \[ - OH\]group at position-2. As it is pretty much clear from the nomenclature itself that the functional group attached to the compound is a hydroxyl group as the compound’s name ends with a suffix \[ - ol\].
In the third compound which is\[m - nitro{\text{ }}aniline\], as we have discussed in the first group which is aniline, one of the functional groups present in the compound is an amine. Another functional group is a nitro-group which is at the meta position. Therefore the compound has two functional groups namely the amine and nitro groups.
For the last option the compound name \[oxalic{\text{ }}acid\]. According to the nomenclature of carboxylic acid, the root word is based on the longest chain of carbon or parent compound and adding the suffix –oic acid. Thus the functional group in \[oxalic{\text{ }}acid\] is a carboxyl group.

Note:
Functional groups are specific groupings of atoms within molecules that have their own characteristic properties, regardless of the other atoms present in the molecule. Some of the examples of functional groups are aldehyde, ketone, alcohol, amines, and carboxylic acid.