# 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

Apr 30, 2015

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

$A {X}_{5} {E}_{0}$ - trigonal bipyramidal - zero lone pairs;
$A {X}_{4} {E}_{1}$ - seesaw - 1 lone pair;
$A {X}_{3} {E}_{2}$ - T-shaped - 2 lone pairs;
$A {X}_{2} {E}_{3}$ - linear - 3 lone pairs;

The only option that matches is trigonal bipyramidal.