﻿458 
  Dr. 
  H. 
  S. 
  Allen 
  on 
  Molecular 
  

  

  Group 
  Vli 
  

  

  In 
  the 
  seventh 
  group 
  the 
  only 
  metallic 
  compounds 
  repre- 
  

   sented 
  are 
  those 
  of 
  manganese. 
  The 
  four 
  salts 
  in 
  question 
  

   give 
  concordant 
  values 
  for 
  v 
  A 
  . 
  The 
  chance 
  of 
  an 
  accidental 
  

   agreement 
  is 
  about 
  1 
  in 
  180. 
  

  

  Group 
  VII. 
  

   Manganese 
  Compounds 
  (N 
  = 
  25). 
  

  

  Name. 
  Formula. 
  N. 
  vXlO 
  -12 
  . 
  Nj/Xl0~ 
  12 
  . 
  

   Manganese 
  

  

  chloride 
  MnCl 
  2 
  59 
  2-252 
  6^x204 
  

  

  fluoride' 
  MnF 
  2 
  43 
  3756 
  8"x20'2 
  

  

  silicate 
  MnSi0 
  3 
  63 
  3057 
  9^x203 
  

  

  sulphate 
  MnS0 
  4 
  73 
  2-107 
  7^x20'5 
  

  

  In 
  the 
  same 
  group 
  are 
  a 
  number 
  of 
  compounds 
  containing 
  

   chlorine 
  or 
  iodine. 
  Most 
  of 
  these 
  require 
  the 
  provisional 
  use 
  

   of 
  frequency 
  numbers 
  of 
  the 
  form 
  n+i 
  or 
  ra 
  + 
  1. 
  

  

  Chlorine 
  and 
  Iodine 
  Compounds. 
  

  

  Chlorosulphonicacid... 
  C1S0 
  2 
  . 
  OH 
  58 
  1-335 
  3|x20-6 
  

  

  Iodine 
  inonochloride 
  «. 
  IOl 
  70 
  1-125 
  3§x21-0 
  

  

  Iodine 
  tetrachloride 
  ... 
  IC1 
  3 
  104 
  0'836 
  4^x205 
  

  

  Iodine 
  fluoride 
  IF 
  5 
  98 
  0-869 
  4 
  x21'3 
  

  

  Iodic 
  acid 
  HI0 
  3 
  78 
  T342 
  5 
  X20'9 
  

  

  Group 
  VIII. 
  

  

  In 
  the 
  eighth 
  group 
  the 
  data 
  are 
  scanty, 
  only 
  six 
  com- 
  

   pounds 
  of 
  iron 
  being 
  represented, 
  two 
  of 
  cobalt, 
  and 
  one 
  

   each 
  of 
  nickel, 
  ruthenium, 
  and 
  osmium. 
  Rhodium, 
  palladium, 
  

   platinum, 
  and 
  iridium 
  are 
  not 
  represented 
  at 
  all. 
  The 
  results, 
  

   as 
  far 
  as 
  they 
  go, 
  tend 
  to 
  show 
  that 
  the 
  compounds 
  of 
  this 
  

   group 
  fall 
  into 
  line 
  with 
  the 
  metallic 
  salts 
  of 
  the 
  earlier 
  groups, 
  

   the 
  only 
  serious 
  discrepancy 
  being 
  the 
  case 
  of 
  cobalt 
  carbonyl 
  

   where 
  it 
  is 
  possible 
  that 
  molecular 
  association 
  occurs. 
  

  

  