Question #fa03c

1 Answer
Dec 18, 2014

Consider the structure of the #"H"_2"S"# molecule:

http://imgarcade.com/1/electron-dot-structure-for-h2s/

The repulsion of the two lone pairs of electrons on the sulfur atom causes the molecule to bend. The more electronegative sulfur atom attracts the bonded electrons more strongly and develops a slight negative charge, while the less electronegative hydrogen atoms develop a slight positive charge, and the molecule forms a dipole, making the molecule polar. #"H"_2"S"# molecules form dipole-dipole attractions with other #"H"_2"S"# molecules, similar to the hydrogen bonds between water molecules, but not as strong, because the oxygen atom is more electronegative than the sulfur atom.

The molecular geometry is important in this case, as it is with water. If #"H"_2"S"# was a linear molecule, it would be a nonpolar molecule.