Question

Based on the VSEPR theory, what is the molecular geometry of a molecule of PI3?

Answer 1

VSEPR Theory allows for the prediction of molecular shapes based on the number of electron pairs that surround their respective atoms.

In order to determine the molecular shape of the `PI_3` molecule using VSEPR Theory, its Lewis structure must first be determined.

SInce `P` has 5 valence electrons, and each `I` atom has 7 valence electrons, the molecule's Lewis structure will look like this:

Notice that `P` uses 3 valence electrons to form covalent bonds with the three `I` atoms, which leaves it with one lone pair of electrons.

`P` has a steric number of 4 and a coordination number of 3, which means that it has a tetrahedral electron geomerty and a trigonal planar molecular geometry.

Here's a representation of `PI_3`'s molecular geometry: