Homework#26

[206190205]

Give the full electron configuration for aluminum (Al).
When writing out the electron configuration why is the 3s orbital bigger that the 2p orbitals?

[305920501]

The number listed before the type of orbital (3 before s, 2 before p) illustrates which valence shell the electrons are in. The 2nd valence shell only has an s and p orbital, and the following shell (3) is larger with an s, p, and d orbital. When you fill the orbitals of an atom, you start at the smallest valence shell and work outwards. The 2nd valence shell comes before the 3rd.