Electronic Configuration

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New theories show that:

Each principle quantum shell consists of energy sub-levels that are labelled s,p,d and f.

The number of sub-levels in a shell depend on the principal quantum shell.

An orbital is the volume of space where there is a 95% chance of finding the electron.

Each orbital can hold 2 electrons. Electrons spin opposite to each other to minimize repulsion.

S sub-level:

There is only one orbital in the s sub-level,which is called the s orbital.

Its shape is spherical.

The nucleus is at the centre of the sphere.

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P orbitals:

There are 3 orbitals in the p-sub-level, which are called p-orbitals.

p orbitals have a dum-bell shape.

These orbitals are located along the x,y and z axis.

Each p orbital can hold 2 electrons.

The 3 p orbitals can hold a total of 6 electrons.

The 5 orbitals of the d sub-level and the 7 of the f sub-level have complicated shapes.

If there are more than one orbital in the same sub-level, the electrons occupy the orbitals singly first, then in pairs.

Electrons go in the orbital with the opposite spin.