Question

# Which of the following is called Westron?A. $C{{H}_{3}}Cl$B. $CHC{{l}_{3}}$C. $HC{{l}_{2}}C-CHC{{l}_{2}}$D. $C{{l}_{2}}C=CHCl$

Hint: Westron is mostly used as an industrial solvent for oil and grease. It is a dense liquid that is not miscible in water and non-polar in nature.

Westron is a pale-yellow liquid that has a high density and is a non-polar solvent. It has many industrial uses as a solvent for oil, grease and fats. It is non-flammable and a toxic substance with a sweet odour. It is classified into the haloalkanes class of compounds.
The preparation of Westron is done by the chlorination of acetylene. It is chlorinated to form a tetrachloro compound. Further chlorination of Westron yields hexachloroethane. This hexachloroethane is further reacted with calcium hydroxide to form westrosol.
The reaction for synthesis of Westron is as follows:
$H-C\equiv C-H+2C{{l}_{2}}\to HC{{l}_{2}}C-CHC{{l}_{2}}$ 1 mole of acetylene or ethyne, combines with 2 moles of chlorine gas to give 1 mole of Westron or tetrachloroethane

The IUPAC name for Westron is 1,1,2,2-tetrachloroethane.
Westron is also used in paints, pesticides (due to its toxic character), and as an organic solvent.
The other options are called as follows:
A. $C{{H}_{3}}Cl$ is known as chloromethane.
B. $CHC{{l}_{3}}$ is known as chloroform, belonging to the haloform class of compounds.
D. $C{{l}_{2}}C=CHCl$ is trichloroethene
Hence, the answer to this question is ‘C. $HC{{l}_{2}}C-CHC{{l}_{2}}$’.

Note: The option ‘D. $C{{l}_{2}}C=CHCl$’ is known as westrosol, but it has only 3 chlorine atoms along with a double bond. Do not confuse the common names of both the compounds.