H2O and H2O intermolecular forces

[Jordan_Wesson_2J]

In my discussion, my TA said that there were dipole-dipole, Van Der Waal, and hydrogen bonds present between two water molecules and I was wondering where each of these would be between the two molecules.

[Andonios Karas 4H]

A hydrogen bond is a dipole-dipole interaction between two water molecules. Due to the differing electronegativies, the oxygen atom will have a slightly negative charge and hydrogen atoms will have slightly positive charges in water. Therefore, water is a dipole as electrons are pulled more towards one atom, oxygen. The slightly negative oxygen atom of one water molecule interacts with the slightly positive hydrogen of another molecule forming a hydrogen bond or interaction between two dipoles.

Van der Waal’s forces occur between any two water molecules through the induced grouping of electrons from molecules coming close together and electrons repelled or attracted to one side of the molecule. If an area of one water molecule has more electrons and is slightly negative charge, it will repel electrons in nearby molecules, creating a slightly positively charged area in the nearby molecules then become attracted. While a weaker force, many of these together can be very strong.