Question

How would you name the following compounds?
i.$\text{C}{{\text{H}}_{\text{3}}}\text{-C}{{\text{H}}_{\text{2}}}\text{-Br}$
ii.$\text{H-CHO}$
iii.$\text{C}{{\text{H}}_{\text{3}}}\text{-}{{\left( \text{C}{{\text{H}}_{\text{2}}} \right)}_{\text{3}}}\text{-CH=C}{{\text{H}}_{2}}$
A.(i) Bromomethane (ii) Methanol (iii) Hexane
B.(i) Bromoethane (ii) Ethanol (iii) Hexane
C.(i) Bromopropane (ii) Methanol (iii) Hexane
D.(i) Bromoethane (ii) Methanal (iii) Hexene

Answer 1

The nomenclature of the organic compound is based on the rules of the International Union of Pure and Applied Chemistry or IUPAC. The halogens are written as prefix while unsaturation and carbonyl groups are written as suffix.

Complete step by step answer:
- In the above compounds, the first compound has two carbon atoms, so the root name of the compound will start with “Eth”. As the compound is an alkyl halide with bromine as the substituent, the full name of the compound will be “Bromoethane”.
- Coming to the second compound, there is only one carbon atom as the carboxyl group in the compound, hence the name of the compound will be “methanal”.
- In the last compound, there are six carbon atoms in the root chain, hence the name of the compound should start with “hex”. As there is one double bond between the first two carbon atoms, so the name will be hex-1-ene or simply hexane.

So, the correct answer to the above question is option D.

Note:
The IUPAC rules for the nomenclature of the organic compounds can be detailed as follows:
1. At first, the carbon chain with the maximum number of carbon atoms is to be chosen which will be denoted as the main of the compound.
2. Seconding the number of the chain is done on the basis of the substituents and the double and triple bonds as well as the presence of the functional groups.