Question

The monohalogen derivatives of alkanes are called?
A. Alkene halide
B. Haloalkanes
C. Halogen alkyl
D. None of the above

Answer 1

Hint: These derivatives contain one or more halogens atoms. Basically, they are a subset of the general class of halocarbons. They are also widely used commercially and are known under many chemical names.

Complete step by step answer:
So, on a general basis saturated hydrocarbon is called alkanes, with the general formula of ${ C }_{ n }{ H }_{ 2n }+2.$

Now, considering the question let us understand a bit more about mono halogen derivatives.
Generally, when one hydrogen atom of an alkane is replaced by a halogen atom, then the compound obtained is called a mono halogen derivative of alkanes. Typically they are called as alkyl halides (depending on the degree of substitution at the carbon atom carrying the halogen, alkyl halides are classified into primary, secondary and tertiary alkyl halides) or halo alkenes.

The general formula is ${ C }_{ n }{ H }_{ 2n+1 }{X}$
Examples are, ${ CH }_{ 3 }CH, { C }_{ 2 }{ H }_{ 5 }Br$ etc.
You should also know that haloalkanes are widely used as flame retardants, fire extinguishants, refrigerants, propellants and as solvents they are also used for dry cleaning and for general degreasing purposes.

Therefore, the mono halogen derivatives of alkanes are called halo alkanes. Hence, option B is the required answer.

Note: You should know that they are used as flame retardants, fire extinguishants, refrigerants, propellants, solvents for dry cleaning and for general degreasing purposes and pharmaceuticals etc.