Question

Which of the following does not have a tetrahedral structure?

• A. $S{O}_4^{2-}$
• B. $S{F}_4$
• C. $S{O}_{2}C{I}_2$
• D. $Se{O}_4^{2-}$

Answer 1

The correct option is A $S{O}_4^{2-}$

1. Draw the correct Lewis structure of SF4. It has one lone pair and four bonds around sulfur.
2. Use VSEPR to find the correct geometry for an atom with five groups around it (trigonal bipyramid).
3. The lone pair will probably be at the most open spot possible, which is one of the three equatorial positions rather than at one of the two axial positions. (120-degree bond angle rather than 90-degrees)

Hence it is not having tetrahedral geometry