Final answer:
The noble gas electron configuration of aluminum (Al) is [Ne] 3s² 3p¹, as shown in option A. This uses the configuration of neon (Ne) to represent the inner-shell electrons and shows aluminum has three valence electrons in the 3s and 3p orbitals.
Step-by-step explanation:
The noble gas electron configuration of aluminum (Al) can be determined by looking at its position in the periodic table and identifying the previous noble gas.
For aluminum, which is element number 13, the nearest noble gas before it in the periodic table is neon (Ne), with the atomic number 10. The full electron configuration of aluminum is 1s²2s²2p⁶3s²3p¹.
When we abbreviate this using the noble gas notation, we replace the configuration of the inner-shell electrons (1s²2s²2p⁶) with [Ne], leading to the configuration [Ne] 3s² 3p¹.
This corresponds to option A. When aluminum forms a cation, Al³⁺, it loses the three valence electrons in the 3s and 3p orbitals, reverting to the electron configuration of Ne, which is 1s²2s²2p⁶.