Whats the difference between electron shells, electron levels, and electron orbitals?

1 Answer
Oct 27, 2016

They are all related but refer to different parts of the electron theory of chemistry.


Electron orbitals are probability areas of finding an electron in a given space. Different electron orbitals have different mathematical formulas giving different shapes and energy levels for the different electron orbitals.

The lowest energy level is the # 1s^2 The 1 s orbital is a spherical orbital in the first electron shell. These two electrons fill the shell or energy space closest to the nucleus.

An electron shell is a space around the nucleus that is filled forces any more electrons further out from the nucleus. As the distance from the nucleus increases the number of electrons needed to fill the shell increases. The first shell needs only 2 electrons, the second and third shells 8. The third and fourth shells 18.

Within the energy shells beyond the first shell there are different forms of orbitals with different energy levels. In the second shell there are the # 2s and 2p# electron orbitals. The 2p shaped like a figure eight have a higher electron energy level than the 2s which is a sphere like the 1s only larger.

The third shell has 3 types of orbitals the 3s ( 1 orbital 2 electrons) the 3p ( 3 orbitals 6 electrons) and the 3d ( 5 orbitals 10 electrons) The initial energy level of the 3d electrons is greater than that of the 4s. This causes the 3d electrons to be in the fourth energy shell.

So the energy level of the electron orbitals affects which electron shell the electrons are most likely to be found in. All three concepts are related and tied together.