Question

How would you name the following compounds?
(i) $CH_3-CH_2-Br$
(ii) ${\text{H - CHO}}$
(iii) $CH_3-(CH_2)_3-CH=CH_2$
(1) (i) Bromomethane (ii) Methanol (iii) Hexene
(2) (i) Bromoethane (ii) ethanol (iii) Hexene
(3) (i) Bromopropane (ii) Methanol (iii) Hexene
(4) (i) Bromoethane (ii) Methanal (iii) Hexene

Answer 1

Hint : We know that a chemical compound can have various acceptable systematic names and the systematic method of naming organic chemical compounds is known as IUPAC nomenclature. Remember that no two chemical compounds can have the same names.

Complete Step By Step Answer:
There are some rules for the nomenclature of organic compounds. In the case of alkanes, the longest hydrocarbon chain is selected as the parent chain. The suffix -ane is used for alkanes, the suffix -ene is used for alkenes and the suffix -yne is used for alkynes. The first compound has two carbon atoms, so we have to use eth. It also has a bromine atom in it, so its name will be bromoethane. The second compound ${\text{H - CHO}}$ has only one carbon atom, so we have to use meth. It also has an aldehyde functional group, so its name will be methanal. The third compound has six carbon atoms, so we have to use hex. It also has a double bond in its structure, so its name will be hexene.
Therefore, option 4 is the correct answer.

Note :
The carbons in the parent chain should be numbered in such a way that we reach the double-bonded or triple-bonded carbon atom earliest. The position of the carbon atom with double bond or triple bond is mentioned in numerals. If there are multiple double bonds in the carbon chain, numerical prefixes like di, tri are used to denote their number.