﻿306 
  S. 
  B. 
  Kuzirian 
  — 
  Use 
  of 
  the 
  Sodium 
  Paratung 
  state. 
  

  

  Superheated 
  steam 
  was 
  found 
  to 
  be 
  the 
  reagent 
  desired. 
  Steam 
  

   in 
  a 
  superheated 
  state 
  attacks 
  the 
  chlorides 
  and 
  bromides. 
  

   From 
  sodium 
  chloride 
  and 
  sodium 
  bromide, 
  for 
  example, 
  a 
  

   metallic 
  oxide 
  is 
  formed 
  and 
  hydrochloric 
  acid 
  and 
  hydrobro- 
  

   mic 
  acid 
  are 
  evolved. 
  The 
  inconvenience 
  of 
  this 
  reaction 
  is 
  

   that 
  at 
  sufficiently 
  high 
  temperature 
  the 
  alkali 
  oxide, 
  as 
  well 
  as 
  

   halogen 
  acids, 
  are 
  volatile, 
  and 
  their 
  products 
  tend 
  to 
  combine 
  

   again 
  to 
  form 
  NaCl 
  and 
  NaBr. 
  If 
  this 
  reaction 
  takes 
  place 
  in 
  

   presence 
  of 
  fused 
  sodium 
  paratungstate, 
  the 
  tungsten 
  trioxide 
  

   will 
  take 
  up 
  the 
  metallic 
  oxide 
  and 
  the 
  acid 
  formed 
  is 
  quickly 
  

   expelled. 
  

  

  The 
  reaction 
  between 
  steam, 
  sodium 
  paratungstate 
  and 
  

   sodium 
  chloride 
  may 
  be 
  represented 
  as 
  follow 
  : 
  

  

  5Na 
  2 
  0.1 
  2 
  W0 
  3 
  + 
  14NaCl 
  + 
  7HOH 
  = 
  12Na 
  2 
  W0 
  4 
  + 
  14HC1. 
  

  

  In 
  preliminary 
  tests 
  the 
  following 
  procedure 
  was 
  used. 
  The 
  

   steam 
  was 
  led 
  from 
  a 
  flask 
  through 
  a 
  platinum 
  tube 
  to 
  the 
  cru- 
  

   cible 
  which 
  contained 
  the 
  fused 
  mass 
  of 
  sodium 
  paratungstate 
  

   and 
  sodium 
  chloride. 
  The 
  platinum 
  tube 
  was 
  heated 
  to 
  red- 
  

   ness, 
  the 
  steam 
  passing 
  through 
  the 
  red 
  hot 
  platinum 
  tube 
  

   became 
  superheated, 
  and 
  the 
  interaction 
  between 
  the 
  steam 
  

   and 
  the 
  chloride 
  resulted 
  in 
  the 
  immediate 
  evolution 
  of 
  hydro- 
  

   chloric 
  acid. 
  

  

  The 
  same 
  effect 
  may 
  be 
  brought 
  about 
  more 
  conveniently 
  

   and 
  with 
  great 
  accuracy 
  by 
  directing 
  a 
  sharp, 
  thin 
  blowpipe 
  

   flame 
  upon 
  the 
  surface 
  of 
  the 
  fused 
  mass 
  of 
  sodium 
  paratung- 
  

   state 
  and 
  chloride, 
  since 
  superheated 
  steam 
  is 
  one 
  of 
  the 
  princi- 
  

   ple 
  combustion 
  products 
  of 
  illuminating 
  gas. 
  The 
  gaseous 
  

   carbon 
  dioxide 
  formed 
  in 
  the 
  interaction 
  is 
  completely 
  expelled 
  

   from 
  the 
  fused 
  mass 
  by 
  the 
  acidic 
  tungstate, 
  as 
  shown 
  in 
  the 
  

   determination 
  of 
  carbonates, 
  and 
  the 
  water 
  vapor 
  formed 
  is 
  

   superheated 
  and 
  ready 
  to 
  take 
  part 
  in 
  the 
  reaction. 
  The 
  thin, 
  

   sharp 
  blowpipe 
  flame 
  serves 
  excellently 
  the 
  double 
  object 
  of 
  

   keeping 
  the 
  mass 
  in 
  quiet 
  fusion 
  and 
  of 
  furnishing 
  superheated 
  

   steam 
  to 
  bring 
  about 
  the 
  desired 
  effect. 
  

  

  The 
  procedure 
  is 
  as 
  follows 
  : 
  A 
  20-gram 
  platinum 
  crucible 
  

   is 
  weighed, 
  and 
  a 
  specified 
  amount 
  of 
  sodium 
  paratungstate 
  is 
  

   introduced, 
  fused 
  with 
  a 
  small 
  sharp 
  blowpipe 
  flame 
  from 
  

   above 
  and 
  kept 
  in 
  fusion 
  for 
  Ave 
  minutes 
  in 
  order 
  to 
  expel 
  by 
  

   the 
  action 
  of 
  steam 
  at 
  high 
  temperature 
  any 
  impurities 
  (e. 
  g. 
  

   chlorine 
  of 
  chlorides) 
  volatile 
  under 
  the 
  conditions. 
  The 
  cru- 
  

   cible 
  and 
  contents 
  are 
  cooled 
  and 
  weighed. 
  Next 
  a 
  weighed 
  

   amount 
  of 
  the 
  salt 
  to 
  be 
  analyzed 
  is 
  introduced, 
  and 
  the 
  mate- 
  

   rial 
  in 
  the 
  crucible 
  is 
  carefully 
  fused 
  with 
  the 
  gentle 
  heat 
  of 
  a 
  

   burner 
  with 
  care 
  to 
  avoid 
  spattering. 
  Then 
  a 
  very 
  small 
  and 
  

   sharp 
  flame 
  of 
  the 
  blowpipe 
  is 
  directed 
  upon 
  the 
  surface 
  of 
  the 
  

  

  