What is the VSEPR shape of the molecule #PF_3#?

1 Answer

The VSEPR shape of the molecule #"PF"_3# is trigonal pyrimidal.

Explanation:

We can use VESPR theory to predict a trigonal pyrimidal shape for the molecule #PF_3# because of its #AX_3E# status.

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VESPR stands for valence shell electron pair repulsion. This theory basically says that bonding and non-bonding electron pairs of the central atom in a molecule will repel (push away from) each other in three dimensional space and this gives the molecules their shape.

We can use the following notations when examining a Lewis structure of a molecule.
A = central atom
X = peripheral atoms
E = non-bonding electron pairs of the central atom

#AX_2# = linear molecule
#AX_3# = trigonal planar
#AX_3E# = trigonal pyrimidal
#AX_2E_2# = bent
#AX_4# = tetrahedral molecule