Electronic Configuration Z Neutral Positive ion ------------------------------------------------------------------------------------------------------------------------------------------------------------- 1 H 1s^1 - 2 He 1s^2 1s^1 3 Li 1s^2 2s^1 1s^2 4 Be 1s^2 2s^2 1s^2 2s^1 5 B 1s^2 2s^2 2p^1 1s^2 2s^2 6 C 1s^2 2s^2 2p^2 1s^2 2s^2 2p^1 7 N 1s^2 2s^2 2p^3 1s^2 2s^2 2p^2 8 O 1s^2 2s^2 2p^4 1s^2 2s^2 2p^3 9 F 1s^2 2s^2 2p^5 1s^2 2s^2 2p^4 10 Ne 1s^2 2s^2 2p^6 1s^2 2s^2 2p^5 11 Na 1s^2 2s^2 2p^6 3s^1 1s^2 2s^2 2p^6 12 Mg 1s^2 2s^2 2p^6 3s^2 1s^2 2s^2 2p^6 3s^1 13 Al 1s^2 2s^2 2p^6 3s^2 3p^1 1s^2 2s^2 2p^6 3s^2 14 Si 1s^2 2s^2 2p^6 3s^2 3p^2 1s^2 2s^2 2p^6 3s^2 3p^1 15 P 1s^2 2s^2 2p^6 3s^2 3p^3 1s^2 2s^2 2p^6 3s^2 3p^2 16 S 1s^2 2s^2 2p^6 3s^2 3p^4 1s^2 2s^2 2p^6 3s^2 3p^3 17 Cl 1s^2 2s^2 2p^6 3s^2 3p^5 1s^2 2s^2 2p^6 3s^2 3p^4 18 Ar 1s^2 2s^2 2p^6 3s^2 3p^6 1s^2 2s^2 2p^6 3s^2 3p^5 19 K 1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 1s^2 2s^2 2p^6 3s^2 3p^6 20 Ca 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 21 Sc 1s^2 2s^2 2p^6 3s^2 3p^6 3d^01 4s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^01 4s^1 22 Ti 1s^2 2s^2 2p^6 3s^2 3p^6 3d^02 4s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^02 4s^1 23 V 1s^2 2s^2 2p^6 3s^2 3p^6 3d^03 4s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^04 24 Cr 1s^2 2s^2 2p^6 3s^2 3p^6 3d^05 4s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^05 25 Mn 1s^2 2s^2 2p^6 3s^2 3p^6 3d^05 4s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^05 4s^1 26 Fe 1s^2 2s^2 2p^6 3s^2 3p^6 3d^06 4s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^06 4s^1 27 Co 1s^2 2s^2 2p^6 3s^2 3p^6 3d^07 4s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^08 28 Ni 1s^2 2s^2 2p^6 3s^2 3p^6 3d^08 4s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^09 29 Cu 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 30 Zn 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^1 31 Ga 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 32 Ge 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^1 33 As 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^3 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^2 34 Se 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^4 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^3 35 Br 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^5 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^4 36 Kr 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^5 37 Rb 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 5s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 38 Sr 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 5s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 5s^1 39 Y 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^01 5s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 5s^2 40 Zr 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^02 5s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^02 5s^1 41 Nb 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^04 5s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^04 42 Mo 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^05 5s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^05 43 Tc 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^05 5s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^05 5s^1 44 Ru 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^07 5s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^07 45 Rh 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^08 5s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^08 46 Pd 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^09 47 Ag 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 48 Cd 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^1 49 In 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 50 Sn 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^1 51 Sb 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^3 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^2 52 Te 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^4 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^3 53 I 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^5 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^4 54 Xe 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^5 55 Cs 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 6s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 56 Ba 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 6s^1 57 La 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 5d^01 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 5d^02 58 Ce 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^01 5d^01 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^01 5d^02 59 Pr 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^03 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^03 6s^1 60 Nd 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^04 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^04 6s^1 61 Pm 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^05 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^05 6s^1 62 Sm 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^06 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^06 6s^1 63 Eu 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^07 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^07 6s^1 64 Gd 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^07 5d^01 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^07 5d^01 6s^1 65 Tb 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^09 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^09 6s^1 66 Dy 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^10 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^10 6s^1 67 Ho 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^11 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^11 6s^1 68 Er 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^12 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^12 6s^1 69 Tm 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^13 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^13 6s^1 70 Yb 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 6s^1 71 Lu 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^01 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 6s^2 72 Hf 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^02 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^01 6s^2 73 Ta 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^03 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^03 6s^1 74 W 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^04 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^04 6s^1 75 Re 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^05 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^05 6s^1 76 Os 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^06 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^06 6s^1 77 Ir 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^07 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^07 6s^1 78 Pt 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^09 6s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^09 79 Au 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 80 Hg 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^1 81 Tl 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 82 Pb 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^1 83 Bi 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^3 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^2 84 Po 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^4 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^3 85 At 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^5 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^4 86 Rn 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^5 87 Fr 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 7s^1 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 88 Ra 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 7s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 7s^1 89 Ac 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 6d^1 7s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 7s^2 90 Th 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 6d^2 7s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 6d^2 7s^1 91 Pa 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 5f^2 6d^1 7s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 5f^2 7s^2 92 U 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 5f^3 6d^1 7s^2 1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6 4d^10 5s^2 5p^6 4f^14 5d^10 6s^2 6p^6 5f^3 7s^2