Question

The volatility of HF is low as compare to other Hydra acid of halogen because of:
A. its low polarizability
B. the weak dispersion interaction between the molecules
C. its molecular mass
D. its strong hydrogen bonding

Answer 1

Hydrogen fluoride is the molecule formed of one hydrogen atom and one fluorine atom. Fluorine is a very electronegative compound whereas the electronegative value of hydrogen is less.

Complete step by step answer:
In the periodic table, the atoms attract the electrons from other atoms towards themselves when they are bonded with another atom.
The atom which attracts the electrons has higher electronegativity value than the atom which shows a low ability to attract electrons.
In hydrogen fluoride molecules, the electronegativity value of hydrogen is 2.2 and the electronegativity value of fluorine is 4.0. Due to the high electronegativity value of fluorine, the fluorine atom strongly attracts the electrons from hydrogen as the electronegativity value of hydrogen is less. As a result, a strong hydrogen bond is formed between the hydrogen atom and fluorine atom.
A hydrogen bond is defined as the intermolecular force that is generated when dipole-dipole attraction takes place between the hydrogen atom and a strongly electronegative atom that exist in the neighboring area of another electronegative atom carrying lone pair of electrons.
Hydrogen fluoride has a strong hydrogen bond that is present, therefore it has low volatility as compared to other Hydra acid of halogen.

Therefore, the correct option is D

Note:
The hydrogen bonds are generally formed due to the lone pairs of electrons present in the highly electronegative atom. Hydrogen bonds are stronger than dispersion forces and dipole-dipole interaction but weaker than ionic bonds and covalent bonds.