Arrange the following compounds in increasing order of their boiling points.

(A) Bromomethane
(B) Bromoform
(C) Chloromethane
(D) Dibromomethane

Choose the correct answer from the options given below:

(C), (A), (D), (B)

The correct answer is Option (2) → (C), (A), (D), (B)

The boiling points of these haloalkanes increase primarily with molecular mass, as higher mass leads to stronger London dispersion forces (van der Waals forces), the dominant intermolecular force here (all are polar, but dispersion dominates with heavier halogens).

• (C) Chloromethane (CH₃Cl): Lowest molecular mass (~50.5 g/mol) → lowest boiling point (~−24°C).
• (A) Bromomethane (CH₃Br): Higher mass (~95 g/mol) than CH₃Cl → higher boiling point (~4°C).
• (D) Dibromomethane (CH₂Br₂): Mass ~174 g/mol → boiling point ~97°C.
• (B) Bromoform (CHBr₃): Highest mass (~253 g/mol) → highest boiling point (~149°C).

Thus, increasing order: (C) < (A) < (D) < (B).