Question

IUPAC name of m-cresol is:

A.Benzene-1,3-diol
B.3-chlorophenol
C.3-methyl phenol
D.3-methoxy phenol

Answer 1

Hint: The basic knowledge about our IUPAC Nomenclature is very important to answer this question. There are set rules in an IUPAC nomenclature to give the name of a compound. IUPAC stands for the international union of pure and applied chemistry.

Complete step by step answer:
IUPAC nomenclature is based on naming a molecule’s longest chain of carbons connected by single bonds, whether in a continuous chain or in a ring. All deviations, either multiple bonds or atoms other than carbon, hydrogen are indicated by prefixes or suffixes, according to a specific set of priorities.
Step 1: The parent chain of the compound contains a benzene ring and an alcohol group. Hence it is named as phenol.
Step2: One substitute is present on the meta side of the ring which the third position from the functional group and it is methyl
     

Step 3: Now from the above 2 steps we can write the name of the compound in the third step that is 
3-methyl phenol
Option A contains two alcohol group, which is not included in cresol ;
Option B contains chlorine, which is not included in cresol ;
Option D contains alkoxy group, which is not included in cresol ;
And hence option C is the correct answer.

Note:
Use the following steps in the series to get an IUPAC name of the compound. First, select the longest carbon chain. Then numbered the chain according to the preference given or priority is given to the functional group. Add the suffixes and prefixes according to the priority of that functional group.