Question

Butanone is a four carbon compound with a functional group:
(A) Carboxylic acid
(B) Aldehyde
(C) Ketone
(D) Alcohol

Answer 1

Hint: We can identify the functional group present in the compound by suitable prefix or suffix used in the name of the compound. Here, -one is the prefix used to indicate the particular functional group.

Complete step by step solution:
We will see how to identify the functional group present in the organic compound.
- We know that organic compounds are named according to IUPAC nomenclature. This nomenclature has certain prefixes and suffixes which indicate the presence of functional groups. It also has some words which describes the number of carbons and its arrangement in the compound.
- The given compound is Butanone.
- In organic chemistry, the word butane shows the presence of four carbons. This is also given in the question.
- We can see that there is a suffix –one after the word ‘butan’. This suffix shows the presence of a functional group.
- Whenever a suffix –one is used, it shows the presence of a ketone functional group. Thus, from the name of this compound, we can say that the compound is a ketone which has a total of four carbons.
- To indicate the presence of a carboxylic acid functional group, the suffix –oic acid is used.
e.g. Butanoic acid
- To indicate the presence of an aldehyde functional group, the suffix –al is used.
e.g. Butanal
- To indicate the presence of an alcohol functional group, the suffix –ol is used.
e.g. Butanol
Thus, we can conclude that the functional group present in the compound is ketone.

So, the correct answer to this question is (C).

Note: If more than one functional group is present in the compound, then we use the suffix of the functional group that has the highest priority and prefixes are used to indicate the presence of other functional groups.