﻿FEB. 
  4, 
  1922 
  ERICKSON 
  : 
  TSCHERMIGITE 
  53 
  

  

  plus 
  AI2O3. 
  The 
  average 
  results 
  on 
  the 
  prepared 
  sodium 
  alum 
  are 
  as 
  

   follows 
  : 
  

  

  TABLE 
  3 
  

   Partial 
  Analysis, 
  Theoretical 
  Composition 
  and 
  Ignition 
  Results 
  of 
  Sodium 
  Alum 
  

  

  Although 
  the 
  ignited 
  residue 
  from 
  the 
  sodium 
  alum 
  contained 
  a 
  

   small 
  quantity 
  of 
  sulfate 
  which 
  compensates 
  for 
  the 
  loss 
  of 
  a 
  small 
  

   quantity 
  of 
  volatilized 
  alkali, 
  the 
  result 
  seems 
  to 
  indicate 
  the 
  forma- 
  

   tion 
  of 
  a 
  sodium 
  aluminate, 
  since 
  in 
  the 
  ignited 
  residue 
  practically 
  all 
  

   of 
  the 
  sulfate 
  radical 
  is 
  volatilized. 
  

  

  The 
  partial 
  elimination 
  of 
  SO3 
  from 
  Na20 
  in 
  the 
  ignited 
  residue 
  of 
  

   tschermigite 
  is 
  thus 
  explained. 
  It 
  is 
  possible 
  that 
  the 
  small 
  amount 
  

   of 
  MgS04 
  in 
  the 
  tschermigite 
  residue 
  reacts 
  in 
  a 
  similar 
  way 
  with 
  the 
  

   AI2O3. 
  However 
  MgS04 
  alone 
  in 
  small 
  quantities 
  will 
  dissociate 
  con- 
  

   siderably 
  into 
  MgO 
  and 
  SO3 
  in 
  the 
  temperature 
  of 
  the 
  ordinary 
  strong 
  

   blast. 
  

  

  The 
  percentage 
  of 
  water 
  was 
  obtained 
  by 
  subtracting 
  the 
  sum 
  of 
  

   the 
  (NH4)20 
  and 
  the 
  volatilized 
  SO3 
  (the 
  total 
  percentage 
  of 
  SO3 
  cor- 
  

   rected 
  for 
  SO3 
  retained 
  in 
  the 
  ignited 
  residue) 
  from 
  the 
  total 
  loss 
  on 
  

   ignition. 
  The 
  average 
  results 
  for 
  tschermigite 
  are 
  tabulated 
  below. 
  

  

  Table 
  4. 
  — 
  Total 
  Water 
  Content 
  of 
  Tschermigite 
  

  

  (NH4)20 
  5 
  .23 
  

  

  Total 
  SO3 
  35.11 
  

  

  SO3 
  retained 
  in 
  the 
  ignited 
  residue. 
  . 
  . 
  . 
  10 
  

  

  Volatilized 
  SO3 
  35 
  .01 
  

  

  40.24 
  

  

  Total 
  loss 
  upon 
  ignition 
  88 
  .06 
  

  

  Subtracting 
  the 
  total 
  of 
  (NH4)20 
  and 
  volatilized 
  SO3 
  40 
  .24 
  

  

  Water 
  by 
  difference 
  47 
  .82 
  

  

  Ignited 
  Residue 
  of 
  Tschermigite 
  

  

  Residue 
  upon 
  ignition 
  11 
  .94 
  per 
  cent 
  

  

  Sum 
  of 
  constituents 
  other 
  than 
  AI2O3 
  . 
  50 
  

  

  AI2O3 
  by 
  difference 
  11 
  .44 
  per 
  cent 
  

  

  AhOb 
  by 
  direct 
  determination 
  1 
  1 
  . 
  57 
  per 
  cent 
  

  

  