Question

Alkyl halides are classified on the basis of:
A. Nature of halide atom
B. Nature of carbon atom
C. Nature of alkyl group
D. None of these

Answer 1

Hint: Alkyl halides are the halogen derivatives of aliphatic hydrocarbons.
They are formed when one or more hydrogen atoms of an aliphatic hydrocarbon are replaced by the same number of halogen atoms.
In haloalkanes or alkyl halides, the halogen atoms are attached to the ${\text{s}}{{\text{p}}^{\text{3}}}$ hybridized carbon of an alkyl group.

Complete step by step answer:
When a carbon atom is attached to only one other carbon atom, it is called a primary carbon atom. When a carbon atom is attached to other carbon atoms on two different sides, it is a secondary carbon and if attached to other carbons on three different sides, it is called a tertiary carbon.
The general formula of alkyl halides or haloalkanes is ${\text{R - X}}$ . In an alkyl halide, the halogen atom X is bonded to an alkyl group R. Alkyl halides form a homologous series with the general formula ${{\text{C}}_{\text{n}}}{{\text{H}}_{{\text{2n + 1}}}}{\text{X}}$ .
The alkyl halides are classified according to the carbon atom to which the halogen is linked. If in an alkyl halide, the halogen is bonded to a primary carbon, then it is called a primary alkyl halide. If the halogen is bonded to a secondary carbon, then it is called a secondary alkyl halide and if the halogen is bonded to a tertiary carbon, then it is called a tertiary alkyl halide respectively.

For example, 1-bromopropane is a primary alkyl halide and 2-chloro-2-methylpropane is a tertiary alkyl halide.


So, option B is correct.

Note:
The alkyl halides are less soluble in water. This is because energy is required to overcome the attraction between the halogen molecule and also to break the hydrogen bonds between the water molecules for alkyl halides to dissolve in water.
But they are soluble in organic solvents because the new forces of attraction set up between alkyl halides and solvent molecules are of the same strength as the forces of attraction being broken.