## Polarity

Shanzey
Posts: 120
Joined: Wed Sep 18, 2019 12:20 am

### Polarity

When labeling the dipole moment on a Lewis structure, how are we able to tell if the structure is polar or nonpolar? How are we able to tell if there is no net dipole?

John Arambulo 1I
Posts: 58
Joined: Sat Jul 20, 2019 12:15 am

### Re: Polarity

You would know based on the electronegativity of the elements by using the periodic trends and also by formal charges because a negative formal charge would mean the electron density his higher around that atom.

Maya Gollamudi 1G
Posts: 100
Joined: Thu Jul 25, 2019 12:15 am

### Re: Polarity

You can compare the electronegativity of the elements using the periodic table- there will be a greater electron density around the element with a higher electronegativity.

Justin Quan 4I
Posts: 104
Joined: Sat Sep 14, 2019 12:17 am

### Re: Polarity

If you see that all the dipole forces cancels out, then the molecule is nonpolar. However, if there is a net dipole moment that's not zero, then you can tell that the molecule is polar.

alex_4l
Posts: 109
Joined: Thu Sep 26, 2019 12:18 am

### Re: Polarity

Also, if the Lewis Structure contains all the same elements then the molecule is nonpolar, but if there is just one difference it can be polar.
For example, if there are 4 Cl attached to a centered Cl, that would have polar bonds but be a nonpolar molecule. But if there are 4 Cl attached to a centered C, that would have polar bonds and be a polar molecule.
It all really depends on the number of polar bonds--if there is an equal number of polar bonds, it's not polar, but if there is an inequality of polar bonds, it's polar.