Question

What geometric arrangement of charge clouds is expected for an atom that has five charge clouds ? A) tetrahedral B) trigonal bipyramidal C) octahedral D) square planar

Answer 1

The answer is D) trigonal bipyramidal.

An atom that is surrounded by 5 regions of electron density will have a steric number equal to 5.

Depending on the value of the coordination number, which expresses the number of atoms with which a central atom forms bonds, you can have the following molecular geometries

`AX_5E_0` - trigonal bipyramidal - zero lone pairs;
`AX_4E_1` - seesaw - 1 lone pair;
`AX_3E_2` - T-shaped - 2 lone pairs;
`AX_2E_3` - linear - 3 lone pairs;

The only option that matches is trigonal bipyramidal.