Skip to content
Question of 112

Q.Explain hybridisation of phosphorous in the formation of PCl5.

Telangana TsbieTelangana Board of Intermediate Education (Intermediate 1st Year) 2018Subjective· 4mImportance★★★★★
0% · 0/112 Questions
🔒 Locked · start free trial →

You're viewing a preview — the full solution, concept, methods & PYQ mapping are locked.

Start your 14-day free trial to unlock the full solution →

One 3s electron of phosphorus is promoted to a 3d orbital, giving five unpaired electrons that hybridize as sp3dsp^3d, producing a trigonal bipyramidal PCl5\text{PCl}_5 molecule.

Ground state electronic configuration of P (Z=15): [Ne] 3s2 3px1 3py1 3pz1[\text{Ne}]\,3s^2\,3p_x^1\,3p_y^1\,3p_z^1 — only 3 unpaired electrons, which would allow only 3 bonds.

Excitation: to form 5 bonds (as needed for PCl5\text{PCl}_5), one electron from the filled 3s3s orbital is promoted to an empty 3d3d orbital. The excited-state configuration becomes:

3s1 3px1 3py1 3pz1 3d13s^1\,3p_x^1\,3p_y^1\,3p_z^1\,3d^1

giving 5 unpaired electrons, each available to pair with an electron from a chlorine atom.

Hybridisation: the one 3s3s, three 3p3p, and one 3d3d orbital mix together to form five equivalent sp3dsp^3d hybrid orbitals. These five hybrid orbitals overlap with the 3p3p orbitals of five chlorine atoms to form five P–Cl sigma bonds.

Geometry: the five sp3dsp^3d hybrid orbitals arrange themselves in a trigonal bipyramidal shape to minimize electron-pair repulsion:

  • 3 orbitals lie in a plane (equatorial), at 120°120° to each other. …

Unlock everything free for 14 days

  • Full step-by-step solutions
  • Concept-first explanations
  • Methods, shortcuts & mistakes
  • PYQ mapping + timed mock tests

Full access for 14 days. No credit card required.