39. Amongst HX, the maximum dipole moment is of a.HBr b.HI c.HF d.HCl
Correct option is A) Dipole moment is a measure of bond polarity which in turn affected by the electronegativity of atoms in the chemical bond. When there is a greater the electronegativity of atom higher will be the dipole moment. Electronigativity of fluorine is highest. So it has more tendency to pull the electrons towards itself than other atoms. In periodic table,down the group electronegativity decreases from top to bottom. So fluorine is most electronegative and iodine is the least electronegative element. So charge polarisation is most in HF and least in HI and hence HF has the highest dipole moment than other element.
