Discuss the hybridization and shape of $PCl_5$.

(N/A) The ground state electron configuration of phosphorus $(P=15)$ is $[Ne] 3s^2 3p^3$.
In the excited state,one electron from the $3s$ orbital is promoted to the $3d$ orbital,resulting in the configuration $[Ne] 3s^1 3p^3 3d^1$.
Hybridization: One $3s$,three $3p$,and one $3d_{z^2}$ orbital mix together to form five equivalent $sp^3d$ hybrid orbitals.
Geometry: These five $sp^3d$ hybrid orbitals are directed towards the corners of a trigonal bipyramid,resulting in a trigonal bipyramidal geometry with bond angles of $120^{\circ}$ and $90^{\circ}$.
Bond Formation: Each of the five $sp^3d$ hybrid orbitals overlaps with the half-filled $p$ orbital of a chlorine atom to form five $P-Cl$ $\sigma$-bonds.