﻿414 
  E. 
  A. 
  Hill 
  — 
  Argon, 
  Front's 
  

  

  necessarily 
  involve 
  monatomicity.* 
  The 
  weak 
  point 
  in 
  the 
  

   assumption 
  that 
  it 
  does, 
  lies 
  in 
  the 
  view 
  taken 
  that 
  the 
  molecular 
  

   encounter 
  involves 
  actual 
  contacts, 
  which 
  is 
  not 
  a 
  necessary 
  

   assumption 
  in 
  the 
  kinetic 
  theory 
  of 
  gases. 
  That 
  such 
  contacts 
  

   do 
  not 
  occur 
  is 
  shown 
  by 
  Maxwell's 
  computations 
  coupled 
  with 
  

   the 
  experiments 
  on 
  viscosity. 
  Moreover, 
  Maxwell 
  did 
  not 
  

   believe 
  in 
  this 
  theory 
  of 
  the 
  encounter, 
  and 
  both 
  Sutherland 
  

   and 
  Pickering 
  assume 
  the 
  existence 
  of 
  a 
  repulsive 
  force. 
  The 
  

   greater 
  the 
  force 
  of 
  aggregation, 
  and 
  the 
  smaller 
  the 
  distance 
  

   between 
  the 
  atoms 
  compared 
  to 
  the 
  imaginary 
  molecular 
  

   diameter 
  or 
  least 
  distance 
  of 
  approach, 
  the 
  less 
  the 
  tendency 
  

   for 
  internal 
  rotation 
  as 
  shown 
  by 
  the 
  application 
  of 
  the 
  astro- 
  

   nomical 
  methods 
  used 
  in 
  the 
  problem 
  of 
  the 
  three 
  bodies. 
  In 
  

   Groups 
  I 
  and 
  VII 
  we 
  have 
  the 
  maximum 
  of 
  atomic 
  volume, 
  

   internal 
  rotation, 
  and 
  chemical 
  activity, 
  combined 
  with 
  small 
  

   heats 
  of 
  dissociation 
  both 
  in 
  solution 
  and 
  otherwise, 
  indicating 
  

   a 
  weak 
  force 
  of 
  aggregation 
  within 
  the 
  molecule. 
  In 
  Groups 
  

   III, 
  IV 
  and 
  VIII 
  we 
  have 
  these 
  properties 
  reversed, 
  small 
  

   volume, 
  little 
  if 
  any 
  internal 
  rotation, 
  chemical 
  inertness, 
  and 
  

   large 
  heats 
  of 
  dissociation 
  indicating 
  a 
  strong 
  force 
  of 
  aggrega- 
  

   tion 
  within 
  the 
  molecule 
  ; 
  and 
  the 
  fact 
  that 
  the 
  translatory 
  

   energy 
  of 
  the 
  H 
  and 
  O 
  molecules 
  before 
  combination 
  is 
  only 
  

   T 
  X 
  oth 
  of 
  their 
  total 
  store 
  of 
  energy, 
  which 
  is 
  not 
  rotational 
  and 
  

  

  * 
  The 
  evidence 
  grows 
  stronger 
  that 
  Argon 
  may 
  be 
  Nitrogen 
  with 
  the 
  molecular 
  

   formula 
  N 
  3 
  , 
  the 
  theoretical 
  density 
  of 
  which 
  (21), 
  would 
  closely 
  agree 
  with 
  

   that 
  (19 
  - 
  9) 
  found 
  for 
  Argon. 
  There 
  would 
  then 
  be 
  more 
  or 
  less 
  analogy 
  between 
  

  

  Oxygen 
  = 
  0, 
  Ozone 
  rf_^Q 
  Nitrogen 
  NEEN, 
  and 
  Argon 
  <r'L^> 
  Thomson 
  

  

  and 
  Threlfall 
  in 
  1886, 
  observing 
  a 
  contraction 
  in 
  volume 
  when 
  the 
  electric 
  spark 
  

   was 
  passed 
  through 
  pure 
  nitrogen, 
  concluded 
  that 
  an 
  allotropic 
  form 
  resulted; 
  

   but 
  Threlfall's 
  later 
  repetition 
  of 
  the 
  experiment 
  led 
  to 
  negative 
  results. 
  John- 
  

   son, 
  from 
  observations 
  on 
  the 
  action 
  of 
  a 
  hot 
  tube 
  upon 
  Nitrogen, 
  also 
  concluded 
  

   that 
  the 
  gas 
  can 
  exist 
  in 
  two 
  forms 
  ; 
  one 
  active, 
  the 
  other 
  inactive. 
  It 
  has 
  been 
  

   recently 
  remarked 
  that 
  as 
  in 
  Ozone, 
  O 
  3 
  , 
  the 
  characteristic 
  properties 
  (chemical 
  

   activity) 
  of 
  Oxygen 
  0- 
  are 
  enhanced 
  ; 
  so 
  in 
  Argon, 
  if 
  it 
  be 
  N 
  3 
  , 
  the 
  characteristic 
  

   property 
  of 
  Nitrogen 
  N' 
  2 
  (its 
  chemical 
  inactivity) 
  should 
  also 
  be 
  enchanced; 
  hence 
  

   its 
  very 
  inert 
  character. 
  The 
  boiling 
  points 
  seem 
  to 
  contradict 
  this 
  view. 
  

   Oxygen— 
  182-2°, 
  Ozone— 
  106-0°, 
  Nitrogen— 
  194*0°, 
  Argon— 
  187-0 
  3 
  . 
  The 
  two 
  

   latter 
  are 
  almost 
  the 
  same, 
  the 
  two 
  former 
  widely 
  separated; 
  but 
  Brauner 
  

   (Chem. 
  News, 
  Feb. 
  15, 
  1895) 
  has 
  endeavored 
  to 
  explain 
  this 
  apparent 
  incon- 
  

   sistency. 
  

  

  Quite 
  recently 
  Berthelot 
  has 
  succeeded 
  in 
  causing 
  combination 
  between 
  Argon 
  

   and 
  the 
  vapor 
  of 
  benzene, 
  by 
  means 
  of 
  the 
  electric 
  spark; 
  thereby 
  producing 
  

   resinous 
  compounds 
  very 
  similar 
  to 
  those 
  produced, 
  under 
  like 
  circumstances, 
  by 
  

   the 
  action 
  of 
  benzene 
  vapor 
  on 
  nitrogen. 
  

  

  In 
  the 
  formula 
  /T'q 
  (Ozone) 
  the 
  molecule 
  is 
  apparently 
  less 
  eccentric 
  than 
  

  

  in 
  0=0 
  (Oxygen) 
  and 
  application 
  of 
  the 
  principles 
  already 
  discussed 
  will 
  show, 
  

   that 
  its 
  tendency 
  for 
  internal 
  rotation 
  should 
  be 
  less 
  than 
  in 
  the 
  case 
  of 
  oxygen. 
  

   I 
  know 
  of 
  no 
  data 
  as 
  to 
  the 
  specific 
  heat 
  ratio 
  for 
  Ozone, 
  but 
  it 
  would 
  be 
  interest- 
  

   ing 
  to 
  know 
  whether 
  or 
  not 
  it 
  is 
  greater 
  than 
  in 
  Oxygen. 
  Evidently 
  if 
  Argon 
  be 
  

   N 
  3 
  we 
  have 
  here 
  another 
  principle 
  tending 
  toward 
  small 
  value 
  of 
  the 
  internal 
  

   energy, 
  and 
  a 
  correspondingly 
  large 
  value 
  in 
  the 
  ratio 
  of 
  the 
  two 
  specific 
  heats. 
  

  

  