What distinguishes #HF#, #H_2O#, and #CH_4# in terms of intermolecular force?

1 Answer
Aug 22, 2016

Answer:

Water has the lowest vapour pressure, the highest viscosity, and the lowest vapour pressure.

Explanation:

These characters can be attributed to the degree of intermolecular forces that operate in each substance. Methane, a room temperature gas, with relatively non-polar #C-H# bonds, has the least degree of intermolecular interaction, even thout the individual #C-H# bonds are strong.

Hydrogen fluoride and water can both support extensive hydrogen bonding due to the polarization of the #H-X# bond and the alignment of dipoles between molecules. This intermolecular force accounts for the elevated boiling points of #HF# (#19.5# #""^@C#) and water, in comparison to the lower Group analogues.