Na, Z= 11
=> 1s2 2s2 2p6 3s1
=> gr I A => metal
Ca, Z = 22
1s2 2s2 2p6 3s2 3p6 4s2
=> gr. ll A => metal
N, Z = 7
1s2 2s2 2p3
=> gr. V A => nemetal
Cl, Z = 17
1s2 2s2 2p6 3s2 3p5
=> gr. VIl A => nemetal
Ag, Z = 47
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 4d10
=> gr. l B => metal