: How can I tell what molecular forces are present?

Question

My chemistry homework has multiple choice questions where I have to look at a compound at choose which molecular forces (London forces, dipole-dipole, hydrogen bonds) are present. I understand what they are, but there is no explanation in my lesson on how I could look at a compound and know what forces it has.

In: Chemistry

Answer 1

Dipole-dipole occurs when there is a large difference in electronegativity, for example in a carbon-chlorine bond.

Hydrogen bonds occur between molecules with O-H bonds, and to a lesser extent N-H.

If neither of these apply, it’s just London forces.