Arrange each set of compounds in order of increasing boiling points.
$(i)$ Bromomethane,Bromoform,Chloromethane,Dibromomethane.
$(ii)$ $1-$Chloropropane,Isopropyl chloride,$1-$Chlorobutane.

(N/A) $(i)$ The boiling point of alkyl halides increases with an increase in the molecular mass (or number of halogen atoms). The order is: $CH_3Cl < CH_3Br < CH_2Br_2 < CHBr_3$.
$(ii)$ For isomers,the boiling point decreases with an increase in branching. For different chain lengths,the boiling point increases with the size of the alkyl group. Thus,the order is: $\text{Isopropyl chloride} < 1-\text{Chloropropane} < 1-\text{Chlorobutane}$.