Electron configuration:
The electron configuration is simply the orientation of electrons about the nucleus of the atom. It is known that the atom structure consists electrons, protons and neutrons. An electron has a negative charge, a proton has a positive charge and is in the nucleus with neutrons. Neutrons have neutral charges (non-charged particles).
In a neutral atom, the number of electrons that electron configuration forms are always equal to the number of protons inside the nucleus. The neutron does not contribute to the electrostatic force which is the force that holds the atom together.
It was found that in the atom structure, electrons tend to orient themselves in a particular fashion. This orientation is called the electron configuration. When atoms get larger and gain more electrons, electrons will exist in particular orbits around the nucleus. A living example of such practice is how each planet in our solar system circles the sun in its own orbit.
In the electron configuration, we find that more than one electron may exist in the same orbit around the nucleus. The first orbital may contain one to two electrons. While the second orbital may contain up to eight electrons. Each subsequent orbital can hold more and more electrons.
Equation for electron configuration
The equation for the number of electrons in each energy level is:
# of electrons = 2(n)^2 Â where “n” is the nth level
For example: Number of electrons in first energy level = 2(1)^2 = 2(1) = 2 electrons
While number of electrons in the second energy level = 2(2)^2 = 2(4) = 8 electrons and so on.
In the electron configuration, an atom is most stable when its outermost orbital is completely full of electrons. In other words two electrons in the first orbital makes the atom more stable than one. While 8 electrons in the second orbital makes it more stable than < 8 electrons.
The orbitals are usually illustrated in two dimensional drawings, in reality the orbitals exist in various three dimensional shapes. Each orbital contains one or more suborbitals identified as s, p, and d. The s, p, and d suborbitals are shaped differently. The shape of the suborbital does not affect the number of electrons in the orbital.