Ground State Electron Configuration of Atoms
| Atomic No. | Element | Configuration | 
|---|---|---|
| 
 1 
  | 
 H 
  | 
 1s1 
  | 
| 
 2 
  | 
 He 
  | 
 1s2 
  | 
| 
 3 
  | 
 Li 
  | 
 [He] 2s1 
  | 
| 
 4 
  | 
 Be 
  | 
 [He] 2s2 
  | 
| 
 5 
  | 
 B 
  | 
 [He] 2s22p1 
  | 
| 
 6 
  | 
 C 
  | 
 [He] 2s22p2 
  | 
| 
 7 
  | 
 N 
  | 
 [He] 2s22p3 
  | 
| 
 8 
  | 
 O 
  | 
 [He] 2s22p4 
  | 
| 
 9 
  | 
 F 
  | 
 [He] 2s22p5 
  | 
| 
 10 
  | 
 Ne 
  | 
 [He] 2s22p6 
  | 
| 
 11 
  | 
 Na 
  | 
 [Ne] 3s1 
  | 
| 
 12 
  | 
 Mg 
  | 
 [Ne] 3s2 
  | 
| 
 13 
  | 
 Al 
  | 
 [Ne] 3s23p1 
  | 
| 
 14 
  | 
 Si 
  | 
 [Ne] 3s23p2 
  | 
| 
 15 
  | 
 P 
  | 
 [Ne] 3s23p3 
  | 
| 
 16 
  | 
 S 
  | 
 [Ne] 3s23p4 
  | 
| 
 17 
  | 
 Cl 
  | 
 [Ne] 3s23p5 
  | 
| 
 18 
  | 
 Ar 
  | 
 [Ne] 3s23p6 
  | 
| 
 19 
  | 
 K 
  | 
 [Ar] 4s1 
  | 
| 
 20 
  | 
 Ca 
  | 
 [Ar] 4s2 
  | 
| 
 21 
  | 
 Sc 
  | 
 [Ar] 3d14s2 
  | 
| 
 22 
  | 
 Ti 
  | 
 [Ar] 3d24s2 
  | 
| 
 23 
  | 
 V 
  | 
 [Ar] 3d34s2 
  | 
| 
 24 
  | 
 Cr 
  | 
 [Ar] 3d54s1 
  | 
| 
 25 
  | 
 Mn 
  | 
 [Ar] 3d54s2 
  | 
| 
 26 
  | 
 Fe 
  | 
 [Ar] 3d64s2 
  | 
| 
 27 
  | 
 Co 
  | 
 [Ar] 3d74s2 
  | 
| 
 28 
  | 
 Ni 
  | 
 [Ar] 3d84s2 
  | 
| 
 29 
  | 
 Cu 
  | 
 [Ar] 3d104s1 
  | 
| 
 30 
  | 
 Zn 
  | 
 [Ar] 3d104s2 
  | 
| 
 31 
  | 
 Ga 
  | 
 [Ar] 3d104s24p1 
  | 
| 
 32 
  | 
 Ge 
  | 
 [Ar] 3d104s24p2 
  | 
| 
 33 
  | 
 As 
  | 
 [Ar] 3d104s24p3 
  | 
| 
 34 
  | 
 Se 
  | 
 [Ar] 3d104s24p4 
  | 
| 
 35 
  | 
 Br 
  | 
 [Ar] 3d104s24p5 
  | 
| 
 36 
  | 
 Kr 
  | 
 [Ar] 3d104s24p6 
  | 
| 
 37 
  | 
 Rb 
  | 
 [Kr] 5s1 
  | 
| 
 38 
  | 
 Sr 
  | 
 [Kr] 5s2 
  | 
| 
 39 
  | 
 Y 
  | 
 [Kr]4d15s2 
  | 
| 
 40 
  | 
 Zr 
  | 
 [Kr] 4d25s2 
  | 
| 
 41 
  | 
 Nb 
  | 
 [Kr] 4d45s1 
  | 
| 
 42 
  | 
 Mo 
  | 
 [Kr] 4d55s1 
  | 
| 
 43 
  | 
 Tc 
  | 
 [Kr] 4d55s2 
  | 
| 
 44 
  | 
 Ru 
  | 
 [Kr] 4d75s1 
  | 
| 
 45 
  | 
 Rh 
  | 
 [Kr] 4d85s1 
  | 
| 
 46 
  | 
 Pd 
  | 
 [Kr] 4d10 
  | 
| 
 47 
  | 
 Ag 
  | 
 [Kr] 4d105s1 
  | 
| 
 48 
  | 
 Cd 
  | 
 [Kr] 4d105s2 
  | 
| 
 49 
  | 
 In 
  | 
 [Kr] 4d105s25p1 
  | 
| 
 50 
  | 
 Sn 
  | 
 [Kr] 4d105s25p2 
  | 
| 
 51 
  | 
 Sb 
  | 
 [Kr] 4d105s25p3 
  | 
| 
 52 
  | 
 Te 
  | 
 [Kr] 4d105s25p4 
  | 
| 
 53 
  | 
 I 
  | 
 [Kr] 4d105s25p5 
  | 
| 
 54 
  | 
 Xe 
  | 
 [Kr] 4d105s25p6 
  | 
| 
 55 
  | 
 Cs 
  | 
 [Xe] 6s1 
  | 
| 
 56 
  | 
 Ba 
  | 
 [Xe] 6s2 
  | 
| 
 57 
  | 
 La 
  | 
 [Xe] 5d16s2 
  | 
| 
 58 
  | 
 Ce 
  | 
 [Xe] 4f15d16s2 
  | 
| 
 59 
  | 
 Pr 
  | 
 [Xe] 4f36s2 
  | 
| 
 60 
  | 
 Nd 
  | 
 [Xe] 4f46s2 
  | 
| 
 61 
  | 
 Pm 
  | 
 [Xe] 4f56s2 
  | 
| 
 62 
  | 
 Sm 
  | 
 [Xe] 4f66s2 
  | 
| 
 63 
  | 
 Eu 
  | 
 [Xe] 4f76s2 
  | 
| 
 64 
  | 
 Gd 
  | 
 [Xe] 4f75d16s2 
  | 
| 
 65 
  | 
 Tb 
  | 
 [Xe] 4f96s2 
  | 
| 
 66 
  | 
 Dy 
  | 
 [Xe] 4f106s2 
  | 
| 
 67 
  | 
 Ho 
  | 
 [Xe] 4f116s2 
  | 
| 
 68 
  | 
 Er 
  | 
 [Xe] 4f126s2 
  | 
| 
 69 
  | 
 Tm 
  | 
 [Xe] 4f136s2 
  | 
| 
 70 
  | 
 Yb 
  | 
 [Xe] 4f146s2 
  | 
| 
 71 
  | 
 Lu 
  | 
 [Xe] 4f145d16s2 
  | 
| 
 72 
  | 
 Hf 
  | 
 [Xe] 4f145d26s2 
  | 
| 
 73 
  | 
 Ta 
  | 
 [Xe] 4f145d36s2 
  | 
| 
 74 
  | 
 W 
  | 
 [Xe] 4f145d46s2 
  | 
| 
 75 
  | 
 Re 
  | 
 [Xe] 4f145d56s2 
  | 
| 
 76 
  | 
 Os 
  | 
 [Xe] 4f145d66s2 
  | 
| 
 77 
  | 
 Ir 
  | 
 [Xe] 4f145d76s2 
  | 
| 
 78 
  | 
 Pt 
  | 
 [Xe] 4f145d96s1 
  | 
| 
 79 
  | 
 Au 
  | 
 [Xe] 4f145d106s1 
  | 
| 
 80 
  | 
 Hg 
  | 
 [Xe] 4f145d106s2 
  | 
| 
 81 
  | 
 Tl 
  | 
 [Xe] 4f145d106s26p1 
  | 
| 
 82 
  | 
 Pb 
  | 
 [Xe] 4f145d106s26p2 
  | 
| 
 83 
  | 
 Bi 
  | 
 [Xe] 4f145d106s26p3 
  | 
| 
 84 
  | 
 Po 
  | 
 [Xe] 4f145d106s26p4 
  | 
| 
 85 
  | 
 At 
  | 
 [Xe] 4f145d106s26p5 
  | 
| 
 86 
  | 
 Rn 
  | 
 [Xe] 4f145d106s26p6 
  | 
| 
 87 
  | 
 Fr 
  | 
 [Rn] 7s1 
  | 
| 
 88 
  | 
 Ra 
  | 
 [Rn] 7s2 
  | 
| 
 89 
  | 
 Ac 
  | 
 [Rn] 6d17s2 
  | 
| 
 90 
  | 
 Th 
  | 
 [Rn] 6d27s2 
  | 
| 
 91 
  | 
 Pa 
  | 
 [Rn] 5f26d17s2 
  | 
| 
 92 
  | 
 U 
  | 
 [Rn] 5f36d17s2 
  | 
| 
 93 
  | 
 Np 
  | 
 [Rn] 5f46d17s2 
  | 
| 
 94 
  | 
 Pu 
  | 
 [Rn] 5f67s2 
  | 
| 
 95 
  | 
 Am 
  | 
 [Rn] 5f77s2 
  | 
| 
 96 
  | 
 Cm 
  | 
 [Rn] 5f76d17s2 
  | 
| 
 97 
  | 
 Bk 
  | 
 [Rn] 5f97s2 
  | 
| 
 98 
  | 
 Cf 
  | 
 [Rn] 5f107s2 
  | 
| 
 99 
  | 
 Es 
  | 
 [Rn] 5f117s2 
  | 
| 
 100 
  | 
 Fm 
  | 
 [Rn] 5f127s2 
  | 
| 
 101 
  | 
 Md 
  | 
 [Rn] 5f137s2 
  | 
| 
 102 
  | 
 No 
  | 
 [Rn] 5f147s2 
  | 
| 
 103 
  | 
 Lr 
  | 
 [Rn] 5f147s27p1 
  | 
| 
 104 
  | 
 Rf 
  | 
 [Rn] 5f146d27s2 
  | 
| 
 105 
  | 
 Db 
  | 
 [Rn] 5f146d37s2 
  | 
| 
 106 
  | 
 Sg 
  | 
 [Rn] 5f146d47s2 
  | 
| 
 107 
  | 
 Bh 
  | 
 [Rn] 5f146d57s2 
  | 
| 
 108 
  | 
 Hs 
  | 
 [Rn] 5f146d67s2 
  | 
| 
 109 
  | 
 Mt 
  | 
 [Rn] 5f146d77s2 
  | 
| 
 110 
  | 
 Ds 
  | 
 [Rn] 5f146d97s1 
  | 
| 
 111 
  | 
 Rg 
  | 
 [Rn] 5f146d107s1 
  | 
| 
 112 
  | 
 Cn 
  | 
 [Rn] 5f146d107s2 
  | 
| 
 113 
  | 
 — 
  | 
 [Rn] 5f146d27s27p1 
  | 
| 
 114 
  | 
 Fl 
  | 
 [Rn] 5f146d27s27p2 
  | 
| 
 115 
  | 
 — 
  | 
 [Rn] 5f146d27s27p3 
  | 
| 
 116 
  | 
 Lv 
  | 
 [Rn] 5f146d27s27p4 
  | 
| 
 117 
  | 
 — 
  | 
 [Rn] 5f146d107s27p5 
  | 
| 
 118 
  | 
 — 
  | 
 [Rn] 5f146d107s27p6 
  | 
| All electron configurations in this table are from experimental determinations except for elements 103-118, which are predicted theoretically. For elements 103-118, only a few atoms can be produced at a time and it is very difficult to determine electron configurations. | ||
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