At normal temperature,iodoform is:

The reagents required for the following two-step transformation are:

The dehydrobromination of $2$-bromobutane results in the formation of which of the following?

Arrange the following in order of $C-Br$ bond strength in a polar solvent. The structures are as follows:
$(I)$ $1$-methylcyclohexa-$2,4$-dienyl bromide
$(II)$ cyclohexa-$2,4$-dienyl bromide
$(III)$ $1$-methylcyclopenta-$2,4$-dienyl bromide
$(IV)$ cyclopenta-$2,4$-dienyl bromide

Nitrochloroform (Chloropicrin) is prepared by the action of chloroform and:

The correct order of $C-X$ bond polarity is: