﻿294 
  Gooch 
  and 
  Walker 
  — 
  Analysis 
  of 
  Iodides. 
  

  

  pound, 
  accompanying 
  the 
  iodate 
  naturally 
  expected, 
  is 
  dis- 
  

   tinctly 
  recognizable 
  when 
  iodine 
  and 
  barium 
  hydroxide 
  inter- 
  

   act 
  at 
  ordinary 
  temperatures. 
  It 
  has 
  been 
  shown, 
  also, 
  in 
  a 
  

   former 
  paper 
  from 
  this 
  laboratory* 
  that 
  free 
  iodine 
  or 
  an 
  iodide 
  

   interacts 
  very 
  easily 
  with 
  iodic 
  acid 
  in 
  the 
  presence 
  of 
  dilute 
  

   hydrochloric 
  acid 
  with 
  the 
  formation 
  of 
  iodine 
  monochloride, 
  

   according 
  to 
  the 
  equations 
  : 
  

  

  HI0 
  3 
  + 
  2T 
  2 
  + 
  5HCI 
  = 
  3H 
  2 
  + 
  5IC1. 
  

  

  II10 
  3 
  + 
  2KI 
  + 
  5HC1 
  = 
  3H 
  2 
  + 
  2KC14-3IC1 
  

  

  Moreover, 
  organic 
  compounds 
  containing 
  the 
  groups 
  —1 
  = 
  

  

  and 
  — 
  I~q, 
  in 
  which 
  iodine 
  seems 
  to 
  be 
  analogous 
  to 
  nitrogen, 
  

  

  result 
  in 
  great 
  variety 
  from 
  the 
  oxidation 
  of 
  halogen 
  substitu- 
  

   tion 
  products. 
  It 
  would 
  seem, 
  therefore, 
  that 
  the 
  formation 
  

   of 
  inorganic 
  reduction 
  products 
  of 
  iodic 
  acid 
  under 
  the 
  condi- 
  

   tions 
  likely 
  to 
  obtain 
  in 
  this 
  analytical 
  process 
  might 
  be 
  by 
  no 
  

   means 
  beyond 
  the 
  bounds 
  of 
  possibility. 
  

  

  A 
  few 
  simple 
  qualitative 
  tests 
  to 
  determine 
  the 
  possibility 
  of 
  

   interaction 
  between 
  small 
  quantities 
  of 
  iodine 
  and 
  iodic 
  acid 
  

   alone 
  met 
  with 
  negative 
  results. 
  Thus, 
  a 
  single 
  drop 
  of 
  

   a 
  decinormal 
  solution 
  of 
  iodine, 
  made 
  as 
  usual 
  in 
  potas- 
  

   sium 
  iodide, 
  gave 
  when 
  added 
  to 
  10 
  cm3 
  of 
  decinormal 
  iodic 
  

   acid 
  a 
  distinctive 
  color 
  to 
  chloroform. 
  Similar 
  results 
  

   were 
  obtained 
  when 
  the 
  iodine 
  was 
  employed 
  in 
  aqueous 
  

   solution 
  in 
  which 
  there 
  was 
  no 
  alkaline 
  iodide. 
  A 
  few 
  

   drops 
  of 
  an 
  aqueous 
  solution 
  of 
  iodine 
  treated 
  (in 
  either 
  

   order) 
  with 
  10 
  cm3 
  of 
  a 
  saturated 
  solution 
  of 
  potassium 
  bicar- 
  

   bonate 
  and 
  10 
  cm3 
  of 
  decinormal 
  iodic 
  acid 
  gave 
  the 
  same 
  dis- 
  

   tinctive 
  color 
  to 
  chloroform 
  as 
  came 
  from 
  the 
  same 
  amount 
  of 
  

   iodine 
  in 
  the 
  absence 
  of 
  the 
  iodic 
  acid. 
  So 
  it 
  appears 
  that 
  if 
  

   in 
  the 
  system 
  under 
  consideration, 
  reactions 
  do 
  occur 
  between 
  

   iodic 
  acid 
  and 
  iodine 
  to 
  alter 
  the 
  amount 
  of 
  iodine 
  recoverable, 
  

   such 
  action 
  is 
  not 
  appreciable 
  between 
  small 
  amounts 
  of 
  these 
  

   materials. 
  This, 
  however, 
  does 
  not 
  preclude 
  the 
  possibility 
  of 
  

   perceptible 
  changes 
  under 
  the 
  mass-action 
  of 
  a 
  large 
  amount 
  of 
  

   iodine. 
  

  

  The 
  reactions 
  of 
  hydrochloric 
  acid, 
  and, 
  probably 
  of 
  hydro- 
  

   bromic 
  acid, 
  in 
  the 
  presence 
  of 
  varying 
  amounts 
  of 
  iodic 
  acid, 
  

   iodine 
  and 
  iodide, 
  as 
  well 
  as 
  the 
  reaction 
  of 
  the 
  alkaline 
  car- 
  

   bonate 
  upon 
  such 
  mixtures 
  are 
  doubtless 
  complex, 
  more 
  or 
  less 
  

   reversible, 
  and 
  dependent 
  upon 
  proportions 
  and 
  dilution. 
  The 
  

   tendency 
  of 
  the 
  former 
  reactions 
  is 
  toward 
  the 
  reduction 
  of 
  the 
  

   molecule 
  of 
  iodic 
  acid, 
  and 
  the 
  formation 
  of 
  the 
  chloride 
  or 
  

   bromide 
  of 
  iodine. 
  Thus, 
  Miss 
  Robertsf 
  demonstrated 
  that 
  a 
  

  

  * 
  Roberts, 
  this 
  Journal, 
  xMii, 
  15*7. 
  f 
  Loc. 
  cit. 
  

  

  