Question #aa9b7

1 Answer
Dylan K.
Dec 7, 2016

OCS is polar
XeF_4 is not polar
NH_3 is most definitely polar

Explanation:

When trying to determine the polarity of a chemical species its important to consider the molecular and electronic geometry of the species and try to map out where exactly the the dipole moment should be (if it exists).

Consider the graphics below:

You could draw a lewis structure for NH_3 like this:
enter image source here

But it's important to realize that it actually looks much more like this geometrically:
enter image source here

With the lone pair on the central species N significantly affecting the polarity of the molecule.

The nitrogen within the molecule is more electronegative and the valence electron about the species will be closer to it than to the hydrogen.

We sometimes write this as delta^- for N and delta^+ for H.

Here are the simple lewis structure for the other species:

enter image source here

enter image source here

I recommend to look at their structure and try to think about the polarity of the species.

Related questions
See all questions in Polarity of Molecules
Impact of this question
3920 views around the world
You can reuse this answer
Creative Commons License