Question

How do dipole dipole forces differ from hydrogen bonds?

Answer 1

Well, hydrogen bonding is a special case of dipole-dipole interaction….

Explanation:

Hydrogen bonding occurs when hydrogen is bound to a strongly electronegative element, i.e. nitrogen, oxygen, or fluorine. Because the heteroatom is POLAR, it acquires a partial negative charge, and we could represent the molecular dipoles as...

`""^(""^+delta)H-F^(delta^-)`, `""^(""^+delta)H_3N^(delta^-)`, or `""^(""^+delta)H_2O^(delta^-)`

...in aggregate, i.e. in the bulk phase, the dipoles line up, and this interaction constitutes a POTENT intermolecular force. And this is expressed by the high normal boiling points of the hydride compounds...water has a ridiculously high boiling point...so does ammonia, at `-33.3` `""^@C`, and so does `HF`, at `+19` `""^@C`. For such SMALL molecules, these volatilities are LOW, and hydrogen-bonding, as a strong intermolecular force of interaction, is responsible.

On the other hand, molecular dipoles result from the chemical bonding of two elements with unequal electronegativities..this leads to some intermolecular interaction, and perhaps elevated boiling points...but with respect to hydrogen bonding we are talking a lower order of magnitude.