Answer to Question #76425 in General Chemistry for Nesha

Question

Rank the following in order of increasing polarity: CH3Cl, CH3F, and CH3Br.

Answer 1

Since F (fluorine) is the most electronegative atom in this case, CH3F will have the greatest dipole moment. Next most electronegative atom is Cl (chlorine), then Br (bromine). The reason why we sort of ignore the C (carbon) and H (hydrogen) atoms here are because they have relatively same electronegativeity values and again, the shape of the molecule entails that a lot of the dipole moment gets canceled between the similar hydrogen atoms.

Hence: CH3F > CH3Cl > CH3Br