# Question 87211

Apr 20, 2017

The electron configuration of the atoms creates the geometry of molecules.

#### Explanation:

Berellium has an electron configuration of  1s^2 2s^2
This configuration allows the electrons to move apart from each other. ( electrons repel each other) The electrons will move as far apart as possible which results in an 180 degree geometry.

Cl- Be - Cl

Oxygen has an electron configuration of $1 {s}^{2} 2 {s}^{2} 2 {p}^{4}$
The three p orbitals are all at right angles to each other. ( x, y and z axis) One of the p orbitals is filled with two electrons. The other two orbitals with a single electron can form bonds initially at 90 degrees.
Because of election repulsion the initial 90 degree angle is deformed to about a 108 degree angle.