Identify the incorrect statement related to PCl5 from the following :
- Axial P–Cl bonds are longer than equatorial P–Cl bonds
- PCl5 molecule is non-reactive
- Three equatorial P–Cl bonds make an angle of 120° with each other
- Two axial P–Cl bonds make an angle of 180° with each other
Answer
(2) PCl5 molecule is non-reactive
Solution
In PCl5, P is sp3d hybridised and the molecule is trigonal bipyramidal.
The three equatorial P–Cl bonds lie in one plane at 120° to each other and the two axial bonds are at 180° to each other statements (3) and (4) are correct.
As per NCERT, the axial bond pairs suffer more repulsion from the equatorial bond pairs, so the axial bonds are slightly longer and hence slightly weaker than the equatorial bonds, which makes PCl5 molecule more reactive.
Statement (1) is correct and statement (2) is incorrect.
Answer: (2)