THE PERIODIC SYSTEM OF THE ELEMENTS 

 (Niels Bohr's Arrangement) 



APPENDIX E 



K^^ 



Electronic Configurations of the Inert Gases 



K 



19 



Rb 



37 



Cs 



55 



87 



Ca 

 20 



Sr 



38 



Atom and 

 atomic number 



Helium (2) 

 Neon (10) 

 Argon (18) 

 Krypton (36) 

 Xenon (54) 

 Radon (86) 



Electrons in quantum groups 

 1st 2nd 3rd 4th 5th 6th 



2 



2 + 



2 + 



2 + 



2 + 



2 + 



+ 8 



+ 18+8 



+ 18 + 18 + 8 



+ 18 + 32 + 18 + 



Ti 



22 



V 



23 



Cr 



24 



Mn Fe Co Ni 



25 26 27 28 



-Transitional Elements ■ 



+ 



Cu Zn Ga Ge 



29 _J 



Y Zr Cb Mo Ma Ru Rh Pd 



9 ^^40^ 41--^ 42^ 43-^ 44^ 45^ 46 



30 31 



32 



As 



33 



Agi Cd 

 47. 1 48, 



Se 



34 



Br 



35 



Kr 

 36 



Ba 

 56 



Ce Pr Yb 



58 59 * 70 



Lu Hf Ta W Re Os Ir Ft 



■ 1\ Jl^ll^l^ 75 76 77 78 



In Sn Sb te I X 



49 50 51 52 53 54 



\ \ 1 



Aui Hg Tl Pb Bi Po - Rn 



79 ; 80 81 82 83 84 85 86 



Ra 



88 



Ac 

 89 



Th 

 90 



Pa 



91 



U 

 92 



Np Pu Am Cm Bk 

 93 94 95 96 97 



Cf 



98 



E 

 99 



Fm Mv No 

 100 101 102 



'Artificial" Elements 



*Rare earths: Nd Pm Sm Eu Gd Tb Dy Ho Er Tm 

 60 61 62 63 64 65 66 67 68 69 



151 



