Question

determine the electron geometry of pf₃. linear pentahedral trigonal planar hexahedral tetrahedral

Explanation:

Step1: Calculate the steric number

The steric number \(SN=\text{number of bonding pairs}+\text{number of lone pairs}\). For \(PF_3\), phosphorus (\(P\)) has 5 valence electrons. Each \(F\) atom forms a single bond with \(P\) (3 bonding pairs). The number of lone pairs on \(P\) is \(\frac{5 - 3\times1}{2}=1\). So \(SN = 3 + 1=4\).

Step2: Determine electron geometry

According to the VSEPR (Valence - Shell Electron - Pair Repulsion) theory, when the steric number \(SN = 4\), the electron geometry is tetrahedral.

Answer:

tetrahedral