Explain the formation of PCl subscript 5 on the basis of hybridisation

Asked by kpbhake | 12th Mar, 2018, 11:45: AM

Expert Answer:

Formation of PCl5 (sp3d Hybridisation)

  • The ground state and the excited state outer electronic configurations of phosphorus (Z = 15) are given below:
  • The formation of five half-filled sp3d hybrid orbitals involves the intermixing of one 3s, three 3p and one 3d orbitals during excitation.
  • They are then organised in a trigonal bipyramidal symmetry. While three orbitals are organised in trigonal planar symmetry, the remaining two are kept perpendicularly above and below this plane.
  • These half-filled sp3d orbitals help phosphorus in forming five σsp3d-p bonds with chlorine atoms. Each chlorine atom makes use of half-filled 3pz orbital for the bond formation.
  • The PCl5 molecule has a trigonal bipyramidal shape with 120° and 90° of ∠Cl–P–Cl bond angles.
 
 
                                         

 

 

Answered by Varsha | 12th Mar, 2018, 03:54: PM