# Dipole Dipole and Lewis Dot structes

1. Sep 20, 2005

### undertow

Why doesn't HOOH dipole dipole forces?

I read that if a molecule has an Oxygen atom, it's likely to have dipole forces. This one only has Dispersion forces.

Also, why does the Lewis structure of this molecule NOT look like this:

2. Sep 21, 2005

### bomba923

Because the dipoles cancel out. (e.g., $$CO_2$$ is nonpolar, but contains polar bonds).

The component dipole moments of $$H_2O_2$$ simply cancel out, and it has no net dipole moment.
You see, hydroxyl groups contain a partially positively charged hydrogen and a partially negatively charged oxygen.

Draw the direction of each dipole moment, and you will have two antiparallel H -|--> O equal in magnitude but opposite in direction (as vectors). As in vector addition, these two dipole moments will cancel each other out (you have a zero vector for net dipole).
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(Hint: Oxygen | $1 s ^2 2 s^2 2 p^4$ )