Select the insecticide from the following.

State the various uses of:
$(i)$ Dichloromethane (Methylene chloride)
$(ii)$ Trichloromethane (Chloroform)
$(iii)$ Tri-iodomethane (Iodoform)
$(iv)$ Tetrachloromethane (Carbon tetrachloride)
$(v)$ Freons

What is the structural formula of $DDT$?

$Chloral + Chlorobenzene \xrightarrow{conc. H_2SO_4} \text{product}$.
The product is :-

The commercial name of trichloroethene is:

$B.H.C.$ is used as