﻿Adsorjjtion 
  of 
  Hydrogen 
  hy 
  Carbon. 
  

  

  929 
  

  

  7*40 
  c.c. 
  ; 
  gas 
  in 
  carbon 
  at 
  5 
  minutes 
  and 
  10 
  hours, 
  28"04 
  c.c. 
  

   (corr.) 
  and 
  30'40 
  c.c. 
  (corr.). 
  Minimum 
  pressure 
  160'5 
  mm., 
  

   corrected 
  for 
  temperature 
  drift 
  155'0 
  mm., 
  and 
  for 
  extra 
  gas 
  

   122*0 
  mm. 
  Therefore 
  the 
  ratio 
  between 
  final 
  and 
  initial 
  

   surface 
  condensation 
  is 
  81 
  per 
  cent. 
  The 
  dissolved 
  hydrogen 
  

   under 
  a 
  pressure 
  of 
  160 
  mm. 
  is 
  thus 
  9*3 
  c.c. 
  (corr.) 
  per 
  

   gram 
  of 
  carbon. 
  

  

  Inaccurate 
  as 
  the 
  absolute 
  values 
  must 
  be^ 
  yet 
  the 
  mathe- 
  

   matical 
  treatment 
  has 
  shown 
  that 
  all 
  the 
  vakies 
  (apart 
  from 
  

   experimental 
  error) 
  are 
  affected 
  by 
  a 
  relative 
  error 
  of 
  the 
  

   same 
  order 
  of 
  magnitude 
  for 
  each 
  case. 
  Thus 
  the 
  relative 
  

   values 
  may 
  be 
  subsequently 
  trustworthy 
  to 
  give 
  an 
  insight 
  

   into 
  the 
  variation 
  of 
  the 
  solubility 
  with 
  the 
  pressure, 
  and 
  

   hence 
  to 
  furnish 
  information 
  with 
  regard 
  to 
  the 
  molecular 
  

   weight 
  of 
  the 
  hydrogen 
  dissolved 
  in 
  the 
  carbon. 
  A 
  large 
  

   part 
  of 
  the 
  inaccuracy 
  must 
  be 
  ascribed 
  to 
  the 
  inconstancy 
  

   of 
  the 
  temperature 
  of 
  the 
  thermostat 
  and 
  to 
  the 
  difference 
  

   of 
  3 
  to 
  4 
  degrees 
  in 
  absolute 
  temperature 
  depending 
  upon 
  

   the 
  liquid 
  air 
  employed 
  in 
  different 
  experiments. 
  Again, 
  the 
  

   formula 
  here 
  employed 
  is 
  not 
  the 
  true 
  absorption 
  formula 
  

  

  but 
  the 
  total 
  sorption 
  formula 
  s/'p 
  — 
  h.x. 
  

  

  The 
  hypotheses 
  between 
  which 
  it 
  is 
  necessary 
  to 
  discriminate 
  

   are 
  that 
  the 
  dissolved 
  hydrogen 
  : 
  (a) 
  is 
  polymerized, 
  (6) 
  has 
  

   the 
  same 
  molecular 
  weight 
  as 
  in 
  the 
  gaseous 
  state, 
  or 
  (c) 
  is 
  

   dissociated 
  into 
  atoms. 
  In 
  the 
  first 
  case 
  the 
  solubility 
  will 
  

   be 
  proportional 
  to 
  the 
  square 
  (or 
  higher 
  power) 
  of 
  the 
  

   pressure, 
  in 
  the 
  second 
  directly 
  proportional, 
  and 
  in 
  the 
  

   third 
  proportional 
  to 
  the 
  square 
  root 
  of 
  the 
  pressure. 
  In 
  

   the 
  following 
  Table 
  a 
  comparison 
  is 
  made 
  between 
  these 
  

   assumptions. 
  

  

  Table 
  XIY. 
  

  

  Pressure. 
  

  

  Solubility 
  observed. 
  

  

  Calculated 
  for 
  

   H. 
  Ho. 
  H4. 
  

  

  19 
  mm. 
  

  

  40 
  c. 
  c. 
  

  

  4-1 
  c.c. 
  19 
  c. 
  c. 
  0-4 
  c.c. 
  

  

  88 
  mm. 
  

  

  8-9 
  c. 
  c. 
  

  

  8-9 
  c. 
  c. 
  8-9 
  c. 
  c. 
  8-9 
  c. 
  c. 
  

  

  160 
  mm. 
  

  

  9-3 
  c. 
  c. 
  

  

  12-0 
  c.c. 
  16-2 
  c.c. 
  29-4 
  c.c. 
  

  

  The 
  results 
  thus 
  lead 
  to 
  the 
  deduction 
  that 
  dissolved 
  

   hvdrogen 
  is 
  split 
  up 
  into 
  atoms, 
  and 
  it 
  further 
  follows 
  that 
  

  

  