﻿the 
  Unit-Steve 
  Theory. 
  

  

  81 
  

  

  Incidentally, 
  nitrogen 
  is 
  shown 
  to 
  possess 
  the 
  volume 
  3 
  S, 
  so 
  

   that 
  H 
  : 
  C 
  : 
  N 
  = 
  1 
  : 
  4 
  : 
  3. 
  

  

  A 
  remarkable 
  result 
  of 
  the 
  above 
  calculations 
  is 
  that 
  no 
  

   allowance 
  for 
  the 
  so-called 
  double 
  bonds 
  is 
  to 
  be 
  made 
  in 
  

   benzene 
  and 
  its 
  homologues. 
  This 
  is 
  especially 
  noticed 
  in 
  an 
  

   extended 
  study 
  of 
  benzene 
  and 
  hexamethylene 
  to 
  be 
  made 
  

   later 
  (see 
  Table 
  XXII.). 
  

  

  The 
  absolute 
  apparent 
  volumes 
  of 
  carbon 
  and 
  hydrogen 
  in 
  

   the 
  compounds 
  included 
  in 
  the 
  table 
  are 
  considerably 
  smaller 
  

   than 
  those 
  found 
  in 
  aliphatic 
  hydrocarbon 
  chains 
  under 
  similar 
  

   circumstances. 
  It 
  is 
  clearly 
  inadmissible 
  to 
  compare 
  their 
  

   volumes, 
  and 
  to 
  work 
  out 
  volume 
  relations, 
  without 
  first 
  

   taking 
  into 
  account 
  their 
  different 
  constitutions 
  : 
  this 
  may 
  be 
  

   done 
  by 
  allowing 
  a 
  definite 
  contraction 
  for 
  ring-structure. 
  

  

  Conclusion. 
  — 
  The 
  relative 
  volumes 
  of 
  C 
  and 
  H 
  are 
  still 
  as 
  

   4 
  : 
  1 
  in 
  the 
  nuclei, 
  but 
  their 
  absolute 
  values 
  differ 
  from 
  those 
  

   in 
  the 
  side 
  chains 
  or 
  in 
  the 
  paraffin 
  hydrocarbons. 
  

  

  (iv.) 
  The 
  Amount 
  of 
  the 
  Contraction 
  in 
  Aromatic 
  Com- 
  

   pounds 
  for 
  Ring-structure 
  at 
  the 
  Boiling-Point. 
  

  

  Because 
  benzene 
  and 
  its 
  derivatives 
  have 
  almost 
  the 
  same 
  

   volumes 
  as 
  those 
  of 
  certain 
  homologous 
  paraffin 
  hydrocarbons, 
  

   Kopp 
  supposed 
  that 
  the 
  apparent 
  atomic 
  volumes 
  of 
  C 
  and 
  

   H 
  at 
  the 
  boiling-point 
  are 
  11 
  and 
  5*5 
  respectively. 
  This 
  

   conclusion 
  no 
  doubt 
  was 
  arrived 
  at 
  because 
  of 
  a 
  similarity 
  

   in 
  the 
  volumes 
  of 
  certain 
  paraffin 
  hydrocarbons 
  and 
  a 
  series 
  

   of 
  homologous 
  benzene 
  derivatives. 
  The 
  above 
  compounds 
  

   are 
  shown 
  in 
  the 
  following 
  table. 
  

  

  Table 
  XIX. 
  

  

  Table 
  of 
  comparison 
  of 
  the 
  Volumes 
  of 
  Aromatic 
  and 
  

   Paraffin 
  Hydrocarbons 
  at 
  the 
  B.P. 
  

  

  Phil. 
  Mag. 
  S. 
  6. 
  Vol. 
  16. 
  No. 
  91. 
  July 
  1^08 
  

  

  Aromatic 
  Compounds. 
  

  

  v. 
  

  

  Paraffins. 
  

  

  V. 
  

  

  Benzene, 
  

  

  Toluene, 
  

  

  m-Xylene, 
  

  

  Mesitylene, 
  

  

  Oymene, 
  

  

  

  96 
  

  

  118-3 
  

   140-0 
  ! 
  

   162-8 
  

   184-5 
  

  

  Butane, 
  

  

  Pentane, 
  

  

  Hexane, 
  

  

  Heptane, 
  

  

  Octane, 
  

  

  sec. 
  Octane 
  

  

  C,H 
  nn 
  ... 
  

  

  95 
  9 
  

   117-8 
  ! 
  

   139-93 
  

   162-66 
  

   186-26 
  ! 
  

   184 
  

  

  C-H 
  s 
  

  

  O-Hn,.. 
  .. 
  

  

  c 
  sH 
  10 
  

  

  C 
  a 
  H 
  12 
  

  

  ^10^14 
  

  

  

  

  

  ' 
  C 
  S 
  H 
  16 
  : 
  

  

  G 
  

  

  