Răspuns:
1s²
2s² 2p⁶
3s² 3p⁶ 3d¹⁰
4s² 4p⁶
5s¹
2+2+6+2+6+10+2+6+1= 37 e => Nr atomic (Z)= 37 (Rb)
b. rsp la a.. 37 electroni
