F
Fe
Al
Pb
Li
Cl
K
N
Ca
H
[ Ar]4s2 3d6
1s2, 2s2, 2p6, 3s2, 3p5
[ Ar]4s1
[ He] 2s1
1s2, 2s2, 2p6,3s2, 3p6, 4s2
1s2, 2s2, 2p3
1s2, 2s2, 2p5
[Xe ] 6s2, 4f14, 5d10, 6p2
1s1
[ Ne] 3s2, 3p1