﻿362 
  Lea 
  — 
  Color 
  Relations 
  of 
  Atoms, 
  Ions 
  and 
  Molecules. 
  

  

  Eleven 
  metals 
  have 
  both 
  one 
  or 
  more 
  colored 
  and 
  one 
  or 
  

   more 
  colorless 
  ions.* 
  For 
  the 
  moment 
  these 
  have 
  been 
  classed 
  

   together 
  with 
  those 
  that 
  have 
  colored 
  ions 
  only, 
  in 
  order 
  to 
  

   divide 
  the 
  entire 
  series 
  into 
  two 
  great 
  classes. 
  

  

  The 
  distinction 
  however 
  between 
  so-called 
  elements 
  having 
  

   none 
  but 
  colored 
  ions 
  and 
  those 
  having 
  both 
  colored 
  and 
  color- 
  

   less 
  is 
  of 
  very 
  great 
  importance 
  and 
  will 
  be 
  fully 
  considered 
  

   further 
  on. 
  

  

  Placing 
  the 
  foregoing 
  in 
  tabular 
  form 
  we 
  have 
  : 
  — 
  

  

  

  f 
  H 
  

  

  1 
  

  

  

  

  ( 
  Ti 
  48 
  

  

  

  Li 
  

  

  7 
  

  

  

  y 
  5i-2 
  

  

  

  Be 
  

  

  9-3 
  

  

  

  Cr 
  52-4 
  

  

  

  B 
  

  

  11 
  

  

  Ions 
  colored, 
  8< 
  

  

  Mn 
  54-8 
  

  

  

  C 
  

  

  12 
  

  

  

  Fe 
  56 
  

  

  

  N 
  

  

  14 
  

  

  

  Co 
  58-6 
  

  

  

  o 
  

  

  16 
  

  

  

  Ni 
  58-6 
  

  

  

  F 
  

  

  19-1 
  

  

  

  k 
  Cu 
  63-3 
  

  

  Ions 
  colorless, 
  1 
  8 
  < 
  

  

  Na 
  

   Mg 
  

  

  23 
  

   24-3 
  

  

  

  " 
  Zn 
  64*9 
  

  

  

  Al 
  

  

  27-3 
  

  

  

  Ga 
  699 
  

  

  

  Si 
  

  

  28 
  

  

  

  Ge 
  72 
  

  

  

  P 
  

  

  31 
  

  

  

  As 
  74-9 
  

  

  

  s 
  

  

  32 
  

  

  Ions 
  colorless, 
  9^ 
  

  

  Se 
  78-9 
  

  

  

  CI 
  

  

  35 
  5 
  

  

  

  Br 
  79-8 
  

  

  

  K 
  

  

  39 
  

  

  

  Rb 
  85*2 
  

  

  

  Ca 
  

  

  40 
  

  

  

  Sr 
  87*2 
  

  

  

  LSc 
  

  

  45 
  

  

  

  Y 
  92-4 
  

  

  f 
  Nb 
  

  

  94' 
  

  

  

  r 
  Ce 
  142 
  

  

  | 
  Mo 
  

  

  95-8 
  

  

  

  Di 
  145 
  

  

  T 
  , 
  -j 
  a 
  Ru 
  103-5 
  

   Ions 
  colored, 
  6<J 
  Rh 
  ]04 
  . 
  1 
  

  

  

  Sm 
  150 
  

   Er 
  169 
  

  

  1 
  Pd 
  

  

  106-2 
  

   101-1 
  

  

  Ions 
  colored, 
  10 
  < 
  

  

  Ta?182 
  

   W 
  184 
  

   Os 
  192 
  

  

  

  r 
  Cd 
  

  

  111-6 
  

  

  

  Ir 
  192-5 
  

  

  

  In 
  

  

  113-4 
  

  

  

  Pt 
  174 
  

  

  

  Sn 
  

  

  117-8 
  

  

  

  Au 
  196-2 
  

  

  

  Sb 
  

  

  122 
  

  

  

  Ions 
  colorless, 
  9 
  < 
  

  

  Te 
  

  

  125 
  

  

  Alternate. 
  

  

  

  I 
  

  

  126-5 
  

  

  { 
  Colorless 
  Hg 
  199-8 
  

  

  

  Cs 
  

  

  132 
  

  

  j 
  Colored 
  Tl 
  203'6 
  

  

  

  Ba 
  

  

  136-8 
  

  

  • 
  Colorless 
  Pb 
  206-4 
  

  

  

  La 
  

  

  139 
  

  

  * 
  

  

  Colored 
  Bi 
  210 
  

  

  

  

  

  Colorless 
  Th 
  233*9 
  

  

  

  

  

  

  Colored 
  

  

  U 
  240 
  

  

  * 
  This 
  expression 
  is 
  used 
  for 
  brevity 
  and 
  with 
  the 
  intention 
  of 
  expressing 
  the 
  

   fact 
  that 
  an 
  elementary 
  ion 
  may 
  assume 
  different 
  colors 
  with 
  different 
  valencies. 
  

  

  