Dipole-Dipole

[Alvaro Chumpitaz 4D]

Im still having a bit of trouble on how to identify dipole moments from a chemical formula? How do you know there are dipole-dipole forces?

[Sahil Jog 1F]

It is particularly difficult to deduce dipole moments by looking at a chemical formula. It would be much more helpful if you drew out the Lewis structure of the molecule and utilizing electronegativity to figure out where the electrons or negative dipole are pulled towards. This would help you understand if a molecule has dipole forces in the first place.

[MMckinney_4H]

What creates the actual dipole is the arrangement of the atoms in the molecule. So, looking at the molecular formula itself is of little help. You should draw out the lewis structure of the molecule and look at the electronegativity difference between atoms that are bonded to each other. This will give you a good idea of whether or not the molecule is dipole. If you have two dipole molecules, you will have dipole-dipole forces.