An atom of neon has two energy levels. The first energy level has two electrons, while the second energy level has eight electrons. Energy levels are shells containing electrons revolving around the nucleus of the atom.
The atomic number of neon is 10, and its electron configuration is 1S2 2S2 2P6, which means it has two and eight electrons in its inner and outer shells, respectively. The first energy level is 1S2, while the second energy level is 2S2 2P6. The S and P are sub-shells within the shell. Both energy levels in neon are complete, and hence it is chemically inert. It is referred to as a noble gas and is placed in group 18 and period 2 of the periodic table of elements. Neon is classified as a non-metal and is a gas at room temperature.