Answer:
1 s, 3 p and 1 d. The 3[tex]p_{x}[/tex], [tex]p_{y}[/tex] and [tex]p_{z}[/tex] are half filled.
Explanation:
In the production of s[tex]p^{3}[/tex]d hybrid orbitals, 1 s, 3 p and 1 d orbitals of approximately the same energy intermix are used to create 5 identical/degenerate hybrid orbitals. These orbitals are arranged to form a trigonal bipyramidal symmetry. Three orbitals are arranged in a trigonal plane and the other two orbitals are arranged up/down the trigonal plane at right angles.
Using P[tex]Cl_{5}[/tex] as an example, its formation requires five unpaired electron, the phosphorus atom was excited and one electron from the 3s filled one of the vacant 3d orbitals. Thus intermixing the orbitals created the s[tex]p^{3}[/tex]d hybrid orbitals with half-filled 3[tex]p_{x}[/tex], [tex]p_{y}[/tex] and [tex]p_{z}[/tex].
