The Lewis structure for water;
![](Water1.GIF)
Water is polar. It has two lone-pairs of electrons on the central atom.
Because the oxygen atom is more electronnegative compared to the hydrogen
atom it has a greater attraction to the electrons in the O-H bond. Additionally
the lone-pairs of electrons on oxygen contribute to locating the partial negative
charge on the oxygen atom in the moelcule. Therefore the hydrogen atoms carry
a partical positive charge.
![](Water2.GIF)
So what happens when several water molecules are located in close proximity?
Can you draw a picture using the Lewis structures depicting the orientation
of three water molecules to each other based on the partial charge carried on
the oxygen and the hydrogen atoms?
Answer.
![](Water3.GIF)
The adjacent water molecules align themselves so that the partial charges
on adjacen molecules can form an attraction. We refer to the attraction between
the lone-pair of electrons (where there is partial negative charge) on the oxygen
atom of a water molecule and the partial positive charge on the hydrogen atom
as a hydrogen-bond.
![](Water4.GIF)
It is important to associate the hydrogen-bond with the intermolecular
attraction between two water molecules, not the O-H covalent bond within (intra)
the water molecule.