Answer:
The answer to your question is given below.
Step-by-step explanation:
Data obtained from the question include:
Sodium, Na => 1s2 2s2 2p6 3s1
Magnesium, Mg => 1s2 2s2 2p6 3s2
Aluminium, Al => 1s2 2s2 2p6 3s2 3p1
Sodium has 1 valence electron. If we remove the valence electron, sodium metal will become an ion. Thus, the electronic configuration becomes
1s2 2s2 2p6.
Magnesium has 2 valence electrons. If we remove the valence electrons, magnesium metal will be an ion. Thus, the electronic configuration becomes
1s2 2s2 2p6.
Aluminium has 3 valence electrons. If we remove the valence electrons, aluminum metal will become an ion. Thus, the electronic configuration becomes
1s2 2s2 2p6.