notasi nomor atom, konfigurasi elektron, elektron valensi 11A 18B 20C 33D 35E 37F 50G

11A = 11Na : [Ne]3s^1 ➡ ev: 1
18B = 18Ar : [Ne] 3s^2 3p^6 ➡ ev : 8
20C = 20Ca : [Ar] 4s^2 ➡ ev : 2
33D = 33As : [Ar] 4s^2 3d^10 4p^3 ➡ ev: 5
35E = 35Br : [Ar] 4s^2 3d^10 4p^5 ➡ ev: 7
37F = 37Rb : [Kr] 5s^1 ➡ ev: 1
50G= 50Sn : [Kr] 5s^2 4d^10 5p^2 ➡ ev: 4

ev=elektron valensi