Question

Give the name of the following functional group
1. $ - {\text{OH}} $
2. $ - {\text{COOH}} $

Answer 1

Hint: A functional group in an organic entity(compound, molecule) is a substitutent that is responsible for the certain chemical property of that compound, Therefore, if two compounds have the same functional group they are more likely to show a similar physical and chemical property.

Complete answer:
In the first case, we have a $ - {\text{OH}} $ group that is the functional group for alcohol. And the suffix ‘-ol’, is added to the IUPAC name if the compound contains this functional group.
In the second case, we have a $ - {\text{COOH}} $ group, which is the functional group for carboxylic acid. And the suffix ‘-oic acid’ is added to the IUPAC name if the compound has this functional group.

Hence, the name for $ - {\text{OH}} $ is alcohol, and the name for $ - {\text{COOH}} $ is carboxylic acid.

Additional Information:
Many other functional groups can play the role of a substitute in the parent chain of an organic compound. E.g:- halogens( prefix chloro for cl, bromo for br, Iodo for I), aldehyde (suffix -al), ketone (-suffix -one), etc. However, if the organic entity has more than 1 functional group then the nomenclature is done following the preference order for the functional group, COOH > $ - {\text{S}}{{\text{O}}_{\text{3}}}{\text{H}} $ > -COOR (R= alkyl group) > -COCl > $ - {\text{CON}}{{\text{H}}_2} $ > -CN > -HC=O > >C=O > -OH > $ {\text{N}}{{\text{H}}_2} $ > >C=C< > -CC-.

Note:
The functional group for carboxylic acid could be confused by the functional group of Ester(-COOR), which is a derivative of the carboxylic acid. And the suffix used for alcohol (-ol) could also be confused by the suffix used for aldehyde (-al).