Question

Identify the incorrect statement related to PCI from the following:

• A. Three equatorial P-Cl bonds make an angle of 120 with each other
• B. Two axial P-Cl bonds make an angle of 180° with each other
• C. Axial P-Cl bonds are longer than equatorial P-Clbonds
• D. PCI5 molecule is non-reactive

Answer 1

The Correct Option is D

To determine the incorrect statement related to the phosphorus pentachloride (PCI₅) molecule, let's analyze each given statement with respect to the molecular geometry and characteristics of PCI₅:

1. Three equatorial P-Cl bonds make an angle of 120° with each other:
   The molecular geometry of PCI₅ is trigonal bipyramidal. In this geometry, the three equatorial P-Cl bonds indeed form 120° angles with each other. Thus, this statement is correct.
2. Two axial P-Cl bonds make an angle of 180° with each other:
   The two axial bonds are aligned linearly opposite each other, forming an angle of 180°. This statement is also correct.
3. Axial P-Cl bonds are longer than equatorial P-Cl bonds:
   In a trigonal bipyramidal geometry, the axial bonds are subject to increased repulsion from the equatorial bonds and hence are slightly longer than the equatorial bonds. This statement is correct.
4. PCI₅ molecule is non-reactive:
   PCI₅ is a reactive molecule. It readily hydrolyzes on contact with water, making it reactive. Therefore, this statement is incorrect.

Thus, the incorrect statement related to PCI₅ is: PCI₅ molecule is non-reactive. This statement contradicts the known chemical properties of PCI₅.