Draw the electronic configuration of a carbon atom in the normal and excited states.

The chemical element carbon (C) is in the second (2) period in the fourth (lV) group. The number of the period shows how many energy levels the element will have. Since the second period, then there will be two levels. The group number shows how many electrons there will be on the external level, the group we have is lV, which means there will be four electrons on the external level.

The first level has only an S orbital, which can contain a maximum of two electrons and is formed like this

The second level has an S orbital and a P orbital. The S orbital always has two electrons, and the P orbital can have from 1 to 6 electrons. After the electrons are distributed to carbon in the first and second S orbitals, 2 electrons remain free, which will be placed in the P orbital. The P orbital has three cells, when they begin to distribute electrons, then no more than one is placed in each cell. When three cells are filled, they begin to distribute the second electron to these cells. There can be no more than two oppositely directed electrons in a cell. The carbon in the P orbital has two electrons, we place them one in each cell. The third cell remains empty.

1S22S22P2

In an excited state, one electron from the 2S orbital passes into the empty third cell of the P orbital. The electronic formula changes:

1S22S12P3