Question

The number of electron pairs in $OS{F}_4$ is

• A. 4
• B. 5
• C. 5.5
• D. 6

Answer 1

The correct option is B

5

As we already know, we will not apply VSEPR theory here, because according to VSEPR Theory,

ep = $\frac{(6+5)}{2}$ = $\frac{11}{2}$

Now, we will apply AVSEPR Theory.

Central atom will be S [Because of the presence of d-orbitals] and In VSEPR Theory, we ignore oxygen.

Therefore, number of Ligands = 4 [only Fluorine's ignoring oxygen]

Valence electrons in S = 6

Therefore, number of electron pairs = $\frac{(6+4+0-0)}{2}$ = 5