Question

Explain why PCl5 is trigonal bipyramidal and IF5 is square pyramidal?

Answer 1

What do we consider in making hybrid orbitals? Sigma bonds, or lone pairs of electrons.

When you add the number of sigma bonds and lone pairs of electrons, they indicate the total number of vertices around the cetral atom.

In PCl5, it comes out to be 5, referring to 5 vertices.

Now the verices shall be arranged in a pattern to have minimum repulsion, resulting in a Trigonal Pyramidal structure.

In IF5, it comes out to be 6, referring to 6 vertices.

Now the vertices shall be arranged in a patter to have minimum repulsion, resulting in Ocrahedral struucture.

But here we have a lone pair which is negligible and not considered in the geometry, thus if we ignore one vertice of an octahedral, we get a Square Pyramidal structure.

Hope this helps, inform of discrepancies.

Mark as brainliest if satisfied.