Polymers and intermolecular bonds

Intermolecular attractions are weak forces which hold neighbouring molecules together.

There are three main types:

1. All molecules will have instantaneous dipole-induced dipole attractions between them. They occur when the random movement of electrons in one molecule induce a dipole in a neighbouring molecule. The two dipoles then attract each other. The strength of the attraction depends upon the size of the molecule.
2. Molecules that are polar will have additional permanent dipole-permanent dipole attractions.
3. In addition, some molecules will be able to hydrogen bond to each other. A positively charged hydrogen in one molecule interacts with a lone pair of electrons on a neighbouring molecule. This is the strongest type of intermolecular attraction.

Now try the following activity.