Question

The molecules having square pyramidal geometry are:

• A. BrF$_5$ & XeOF$_4$
• B. SbF$_5$ & XeOF$_4$
• C. BrF$_5$ & PCl$_5$
• D. SbF$_5$ & PCl$_5$

Hint:

Understanding electron domain geometry and molecular geometry through VSEPR theory can predict and explain the shapes of complex molecules.

Answer 1

The Correct Option is A

Let's determine the geometry of each molecule:

1. $ BrF_5 $: Bromine has 7 valence electrons. In $ BrF_5 $, there are 5 bond pairs and 1 lone pair. This gives a steric number of 6, which corresponds to an octahedral electron geometry. With 5 bonding pairs and 1 lone pair, the molecular geometry is square pyramidal.

2. $ XeOF_4 $: Xenon has 8 valence electrons. In $ XeOF_4 $, there is one double bond to oxygen and four single bonds to fluorine. There is also one lone pair. This results in a steric number of 6, corresponding to octahedral electron geometry. With 5 bonding pairs and 1 lone pair, the molecular geometry is also square pyramidal.

3. $ SbF_5 $: Antimony has 5 valence electrons. In $ SbF_5 $, there are 5 bond pairs and no lone pairs. The steric number is 5, which corresponds to a trigonal bipyramidal electron and molecular geometry.

4. $ PCl_5 $: Phosphorus has 5 valence electrons. In $ PCl_5 $, there are 5 bond pairs and no lone pairs. The steric number is 5, which corresponds to a trigonal bipyramidal electron and molecular geometry.

Conclusion: Among the given molecules, only $ BrF_5 $ and $ XeOF_4 $ have square pyramidal geometry.

Final Answer:
The final answer is $ BrF_5\ \&\ XeOF_4 $.