Question

The number of molecules having one lone pair of electrons on the central atom is from the following list: SnCl$_2$, XeF$_6$, SO$_3$, ClF$_3$, BrF$_5$, H$_2$O, XeO$_3$. 

• A. 3
• B. 4
• C. 5
• D. 2

Hint:

To determine the number of lone pairs on the central atom, consider the electron domain geometry and the molecular geometry, where lone pairs affect the molecular shape.

Answer 1

The Correct Option is C

Examining each molecule for the presence of a lone pair on the central atom:
- SnCl$_2$: Bent geometry with one lone pair on Sn.
- XeF$_6$: Distorted octahedral geometry with one lone pair on Xe.
- SO$_3$: Trigonal planar with no lone pairs on S.
- ClF$_3$: T-shaped with one lone pair on Cl.
- BrF$_5$: Square pyramidal with one lone pair on Br.
- H$_2$O: Bent geometry with two lone pairs on O.
- XeO$_3$: Pyramidal with one lone pair on Xe.
Molecules with exactly one lone pair on the central atom are SnCl$_2$, XeF$_6$, ClF$_3$, BrF$_5$, and XeO$_3$, totaling five.