﻿546 
  Van 
  Name 
  and 
  Hill 
  — 
  Alcohol 
  and 
  Cane 
  Sugar. 
  

  

  On 
  the. 
  basis 
  of 
  these 
  figures 
  we 
  have 
  taken 
  the 
  value 
  — 
  0*05 
  as 
  

   the 
  correction 
  for 
  evaporation 
  of 
  iodine. 
  By 
  combining 
  this 
  

   with 
  the 
  corrections 
  for 
  loss 
  of 
  solvent, 
  determined 
  as 
  above 
  

   described, 
  we 
  have 
  calculated 
  the 
  following 
  corrections 
  for 
  the 
  

   net 
  result 
  of 
  evaporation 
  under 
  average 
  atmospheric 
  condi- 
  

   tions 
  : 
  

  

  No 
  alcohol 
  Alcohol, 
  \ 
  molar 
  \ 
  molar 
  1-molar 
  2-molar 
  3-molar 
  

   — 
  0-05 
  —0-04 
  —0-02 
  0-00 
  +0*04 
  + 
  0-07 
  

  

  These 
  corrections 
  have 
  been 
  applied 
  in 
  calculating 
  the 
  values 
  

   of 
  Il 
  2 
  , 
  the 
  corrected 
  velocity 
  constant, 
  as 
  given 
  in 
  Tables 
  I, 
  II 
  

   and 
  III. 
  

  

  The 
  cane 
  sugar 
  used 
  was 
  the 
  kind 
  sold 
  in 
  large 
  crystals 
  by 
  

   confectioners 
  under 
  the 
  name 
  " 
  Rock 
  Candy." 
  To 
  eliminate 
  

   any 
  possibility 
  of 
  appreciable 
  inversion 
  of 
  the 
  sugar 
  the 
  con- 
  

   centration 
  of 
  sulphuric 
  acid 
  was 
  reduced 
  in 
  the 
  sugar 
  experi- 
  

   ments 
  to 
  0001 
  molar. 
  As 
  shown 
  in 
  a 
  previous 
  paper* 
  this 
  

   change 
  in 
  the 
  acidity 
  should 
  make 
  no 
  appreciable 
  difference 
  in 
  

   the 
  value 
  of 
  the 
  velocity 
  constant. 
  

  

  The 
  samples 
  of 
  both 
  sugar 
  and 
  alcohol 
  employed 
  were 
  care- 
  

   fully 
  tested 
  as 
  to 
  their 
  effect 
  upon 
  the 
  permanency 
  of 
  the 
  

   standard 
  of 
  an 
  iodine 
  solution. 
  Neither 
  showed 
  any 
  measurable 
  

   effect 
  under 
  conditions 
  of 
  concentration 
  comparable 
  with 
  those 
  

   in 
  the 
  subsequent 
  experiments, 
  even 
  after 
  standing 
  over 
  night. 
  

  

  Experimental 
  Results, 
  and 
  Discussion. 
  

  

  The 
  observed 
  velocity 
  constants 
  are 
  recorded 
  in 
  Tables 
  I, 
  

   II 
  and 
  III. 
  It 
  will 
  be 
  noticed 
  that 
  in 
  nearly 
  every 
  case 
  the 
  

   constants 
  show 
  a 
  tendency 
  to 
  diminish 
  in 
  value 
  during 
  the 
  

  

  Table 
  I. 
  

   No 
  Alcohol 
  or 
  Cane 
  Sugar. 
  

  

  Ki= 
  velocity 
  constant 
  as 
  observed, 
  uncorrected. 
  iT 
  2 
  = 
  constant 
  after 
  cor- 
  

   rection 
  for 
  variation 
  in 
  the 
  rate 
  of 
  stirring 
  and 
  for 
  evaporation. 
  K 
  = 
  most 
  

   probable 
  value 
  by 
  extrapolation. 
  

  

  K 
  

   1. 
  v= 
  580 
  560 
  540 
  520 
  500 
  480 
  460 
  cc 
  ") 
  

   ^t— 
  10 
  10 
  10 
  10 
  10 
  10 
  io 
  min 
  I 
  

  

  c=42*65;37'60; 
  32*99; 
  28*84; 
  25*09; 
  21*76; 
  18*77; 
  16*08 
  j>7*30 
  

  

  

  K 
  = 
  7*30 
  

  

  7*32 
  

  

  7-25 
  

  

  7-24 
  

  

  711 
  

  

  7*10 
  

  

  7-11 
  

  

  | 
  

  

  

  5=7-81 
  

  

  7*26 
  

  

  7-20 
  

  

  7-17 
  

  

  7-10 
  

  

  7*04 
  

  

  7-09 
  

  

  J 
  

  

  2. 
  

  

  K= 
  7-29 
  

  

  7*28 
  

  

  7-25 
  

  

  7-24 
  ■ 
  

  

  7*25 
  

  

  7*15 
  

  

  7*24 
  

  

  7'27 
  

  

  3. 
  

  

  K^ 
  7*24 
  

  

  7*34 
  

  

  7-19 
  

  

  7-14 
  

  

  7*26 
  

  

  7*07 
  

  

  7*21 
  

  

  7-30 
  

  

  4. 
  

  

  K 
  9 
  = 
  7*07 
  

  

  7-10 
  

  

  7*05 
  

  

  6-93 
  

  

  7*05 
  

  

  G*96 
  

  

  6*88 
  

  

  711 
  

  

  5. 
  

  

  5=7*11 
  

  

  7*19 
  

  

  7-09 
  

  

  7*04 
  

  

  6*89 
  

  

  7*10 
  

  

  6*83 
  

  

  714 
  

  

  6. 
  

  

  5= 
  703 
  

  

  7*16 
  

  

  7-04 
  

  

  7*06 
  

  

  6-95 
  

  

  7*05 
  

  

  6*85 
  

  

  7-13 
  

  

  7. 
  

  

  5= 
  7*23 
  

  

  7-19 
  

  

  7-14 
  

  

  7-16 
  

  

  7*09 
  

  

  6*93 
  

   Avei 
  

  

  7-10 
  

   age... 
  

  

  7-22 
  

   . 
  7-21 
  

  

  This 
  Journal, 
  xxxii, 
  211. 
  

  

  