How many hybrid orbitals are present in the molecule PCl5?

1 Answer
May 24, 2014

Answer:

There are no atomic hybrid orbitals in "#PCl"_5#.

Explanation:

A better question might be, "How many hybrid orbitals does a #"P"# atom use when it forms a molecule of #"PCl"_5#?

VSEPR theory predicts that #"PCl"_5# should have a trigonal bipyramidal structure, which corresponds to an #"sp"^3"d"# hybridization.

www.chemistryland.com
(Adapted from SlidePlayer)

The #"P"# atom has five hybridized orbitals.

We usually show the #"P-Cl"# bond as being formed by the overlap of a phosphorus #"sp"^3"d"#orbital with a \chlorine #"3p"# orbital.

Overlap
(Adapted from SlidePlayer)

However, once a #"P-Cl# bond has formed, the original atomic orbitals no longer exist.

They have become σ molecular orbitals.

Thus, the #"PCl"_5# molecule has no hybridized atomic orbitals.