﻿Gooch 
  and 
  Walker 
  — 
  Analysis 
  of 
  Iodides. 
  

  

  299 
  

  

  acidifying, 
  by 
  the 
  interaction 
  of 
  the 
  free 
  iodine, 
  the 
  iodic 
  

   acid, 
  and 
  the 
  hydrochloric 
  or 
  hydrobromic 
  acid, 
  according 
  to 
  

   the 
  reactions 
  previously 
  discussed. 
  It 
  is 
  plain, 
  therefore, 
  that 
  

   the 
  value 
  of 
  the 
  process 
  in 
  the 
  determination 
  of 
  iodine 
  in 
  

   an 
  iodide 
  is 
  restricted 
  of 
  necessity 
  to 
  those 
  cases 
  in 
  which 
  it 
  is 
  

   known 
  that 
  chlorides 
  or 
  bromides 
  are 
  not 
  present 
  to 
  any 
  con- 
  

   siderable 
  extent. 
  For 
  determining/ 
  the 
  standard 
  of 
  a 
  solution 
  

   of 
  nearly 
  pure 
  potassium 
  iodide, 
  employed 
  in 
  so 
  many 
  labora- 
  

   tory 
  processes, 
  it 
  should 
  find 
  useful 
  application. 
  

  

  

  

  Table 
  IV. 
  

  

  

  

  

  Analysis 
  of 
  

  

  Pure 
  Potassium 
  

  

  Iodide. 
  

  

  

  KI 
  taken. 
  

  

  KI 
  found 
  

  

  Error. 
  

  

  

  grm. 
  

  

  grm. 
  

  

  grm. 
  

  

  (1) 
  

  

  0-0814 
  

  

  0-0816 
  

  

  

  

  0002 
  + 
  

  

  (2) 
  

  

  0-0814 
  

  

  0-0813 
  

  

  

  

  0001 
  — 
  

  

  (3) 
  

  

  0-0814 
  

  

  0-0805 
  

  

  

  

  0009 
  — 
  

  

  (*) 
  

  

  0-0815 
  

  

  0-0809 
  

  

  

  

  0006- 
  

  

  (5) 
  

  

  0-0814 
  

  

  0-0808 
  

  

  

  

  0006 
  — 
  

  

  («) 
  

  

  00814 
  

  

  0-0806 
  

  

  

  

  0008 
  — 
  

  

  (<) 
  

  

  0-0814 
  

  

  0-0812 
  

  

  

  

  0002 
  — 
  

  

  (8) 
  

  

  0-1628 
  

  

  0-1624 
  

  

  

  

  0004 
  — 
  

  

  (9) 
  

  

  0-1628 
  

  

  0-1617 
  

  

  

  

  0011 
  — 
  

  

  (10) 
  

  

  0-1628 
  

  

  0-1621 
  

  

  

  

  0007 
  — 
  

  

  (") 
  

  

  0-1628 
  

  

  0-1619 
  

  

  

  

  0009 
  — 
  

  

  (12) 
  

  

  0-1628 
  

  

  0-1624 
  

  

  

  

  0004 
  — 
  

  

  (13) 
  

  

  0-1628 
  

  

  0*1621 
  

  

  

  

  0007 
  — 
  

  

  (14) 
  

  

  0-1628 
  

  

  0-1626 
  

  

  

  

  0002 
  — 
  

  

  (15) 
  

  

  0-2442 
  

  

  0-2451 
  

  

  

  

  0009 
  + 
  

  

  (16) 
  

  

  0-2442 
  

  

  02442 
  

  

  

  

  0000 
  

  

  (17) 
  

  

  0-2442 
  

  

  0-2439 
  

  

  

  

  0003 
  — 
  

  

  (18) 
  

  

  0-3256 
  

  

  0-3258 
  

  

  

  

  0002 
  + 
  

  

  (19) 
  

  

  0-3256 
  

  

  0-3256 
  

  

  

  

  0000 
  

  

  (20) 
  

  

  0-3256 
  

  

  0-3258 
  

  

  

  

  0002 
  + 
  

  

  (21) 
  

  

  0-3256 
  

  

  0-3272 
  

  

  

  

  0016 
  + 
  

  

  (22) 
  

  

  0-3256 
  

  

  0-3256 
  

  

  

  

  0000 
  

  

  (23) 
  

  

  0-4071 
  

  

  0-4076 
  

  

  

  

  0005 
  + 
  

  

  (24) 
  

  

  0-4071 
  

  

  0-4080 
  

  

  

  

  0009 
  + 
  

  

  (25) 
  

  

  0-4071 
  

  

  0-4073 
  

  

  

  

  0002 
  + 
  

  

  In 
  Table 
  TV 
  are 
  comprised 
  a 
  number 
  of 
  experiments 
  made 
  

  

  exactly 
  like 
  those 
  which 
  seemed 
  to 
  give 
  the 
  best 
  results 
  in 
  the 
  

  

  series 
  of 
  Table 
  II. 
  The 
  iodide 
  and'an 
  excess 
  of 
  iodate 
  (5 
  cm3 
  of 
  

  

  N 
  

   the 
  - 
  5 
  per 
  cent 
  solution 
  to 
  every 
  20 
  cmS 
  of 
  — 
  iodide) 
  were 
  made 
  to 
  

  

  interact 
  in 
  a 
  volume 
  of 
  about 
  150 
  cm3 
  , 
  5 
  cm3 
  of 
  sulphuric 
  acid 
  

   (1 
  : 
  3), 
  were 
  used 
  to 
  bring 
  about 
  the 
  reaction, 
  10 
  cm3 
  of 
  potassium 
  

   bicarbonate 
  were 
  added 
  after 
  the 
  neutralization 
  of 
  the 
  sulphu- 
  

  

  