What is the electron configuration representing an atom of aluminum in an excited state?

1 Answer

An example of the electron configuration of aluminum in an excited state is #"1s"^2 "2s"^2 "2p"^6 "3s"^1 "3p"^2#.

Explanation:

There are an infinite number of possible excited states for the valence electrons of aluminum, depending on how much energy the electrons have absorbed.

The ground state of aluminum is #"1s"^2 "2s"^2 "2p"^6 "3s"^2 "3p"^1#

In the ground state the #"3s"# electrons are unable to form bonds. They must absorb energy to move to a higher energy state so that the electrons can be used to form bonds.

What happens is that the atom will promote a #"3s"# electron to the empty #"3p"# orbital, forming an excited state.

The atom can then form 3 #"sp"^2# hybrid orbitals to form three bonds to other atoms.

This enables aluminum to achieve a more stable electron configuration like that of neon.