﻿554 
  Van 
  Name 
  and 
  Hill 
  — 
  Alcohol 
  and 
  Cane 
  Sugar. 
  

  

  larger 
  than 
  would 
  be 
  predicted 
  from 
  the 
  diffusion 
  data, 
  while 
  

   the 
  entrance 
  of 
  this 
  new 
  factor 
  would 
  account 
  for 
  the 
  observed 
  

   deviations 
  from 
  the 
  form 
  of 
  Arrhenius' 
  equation. 
  

  

  In 
  general, 
  if 
  one 
  grants 
  the 
  existence 
  of 
  a 
  diffusion 
  layer 
  it 
  

   is 
  hard 
  to 
  avoid 
  the 
  conclusion 
  that 
  its 
  thickness 
  would 
  vary 
  

   somewhat 
  with 
  the 
  viscosity. 
  The 
  influence 
  of 
  a 
  variation 
  of 
  

   this 
  kind 
  seems 
  to 
  be 
  perceptible 
  in 
  the 
  experimental 
  results 
  of 
  

   this 
  investigation. 
  

  

  Summary. 
  

  

  1. 
  The 
  effect 
  of 
  various 
  concentrations 
  of 
  ethyl 
  alcohol, 
  and 
  

   of 
  cane 
  sugar, 
  upon 
  the 
  rate 
  of 
  solution 
  of 
  cadmium 
  in 
  an 
  

   iodine-potassium 
  iodide 
  solution, 
  has 
  been 
  measured 
  at 
  25°. 
  

  

  2. 
  With 
  alcohol 
  the 
  observed 
  velocity 
  constants 
  agree 
  well 
  

   with 
  the 
  constants 
  calculated 
  from 
  Arrhenius' 
  equation 
  for 
  the 
  

   effect 
  of 
  a 
  non-electrolyte 
  upon 
  the 
  diffusion 
  of 
  electrolytes, 
  if 
  

   an 
  arbitrary 
  though, 
  so 
  far 
  as 
  can 
  be 
  judged 
  by 
  analogy, 
  not 
  

   impossible 
  value 
  is 
  chosen 
  for 
  the 
  constant 
  a 
  in 
  that 
  equation. 
  

  

  3. 
  With 
  cane 
  sugar 
  the 
  observed 
  results 
  cannot 
  be 
  brought 
  

   into 
  good 
  agreement 
  with 
  Arrhenius' 
  equation 
  by 
  any 
  value 
  

   of 
  a. 
  

  

  4z. 
  In 
  both 
  cases, 
  but 
  especially 
  in 
  that 
  of 
  the 
  sugar, 
  the 
  depres- 
  

   sion 
  of 
  the 
  reaction 
  velocity 
  appears 
  to 
  be 
  larger 
  than 
  would 
  

   be 
  expected 
  from 
  the 
  available 
  diffusion 
  data. 
  

  

  5. 
  The 
  probable 
  effect 
  of 
  an 
  increase 
  in 
  viscosity 
  in 
  increas- 
  

   ing 
  the 
  thickness 
  of 
  the 
  diffusion 
  layer 
  is 
  discussed, 
  and 
  is 
  

   suggested 
  as 
  a 
  possible 
  explanation 
  of 
  the 
  discrepancies. 
  

  

  