When full, the innermost electron shell of argon contains how many electrons, and the outermost shell contains how many electrons?
2 and 8
The KLMN electron configuration of Argon is 2, 8, 8 each number referring to the electrons in the shells or energy levels of the atom. Depending on your level of study, we have 2 in the first shell and 8 in the outer two.
If you're studying past GCSE/about 16 years old, you learn about s and p orbitals etc.