208 
DE.  H.  DEBUS  OJT  THE  ACTIOH  OF  AMAIOKLA  OX  GLTOXAL. 
rated  on  the  water-bath  till  all  the  ammonia  has  been  driven  off.  The  remaining  liquid 
is  then  mixed  with  about  twice  its  bulk  of  a warm  and  concentrated  solution  of  oxalic 
acid,  and  the  mixture  allowed  to  stand  for  a few  hours ; crystals  of  oxalate  of  glyoxaline 
are  formed.  They  are  redissolved  in  water,  the  solution  is  decolori2ed  with  charcoal, 
concentrated  by  evaporation,  and  left  in  • a cold  place  to  crystallize.  After  this 
treatment  has  been  repeated  once  or  twice,  crystals  of  pure  binoxalate  of  glyoxaline, 
C3  H4  Ng,  C2  O4,  are  obtained.  It  forms  small  colourless  prisms  much  more  soluble 
in  hot  than  in  cold  water.  A warm  concentrated  solution  crystallizes  during  filtration. 
Analysis  gave  the  following  results : — 
0-321  grm.,  dried  over  sulphuric  acid  and  burnt  with  chromate  of  lead,  gave  0-454  grm. 
carbonic  acid  and  0-117  grm.  water. 
0-466  grm.,  treated  according  to  Will  and  Vaeeenteapp’s  method,  gave  1-322  gnn. 
chloroplatinate  of  ammonium.  The  latter  left  after  ignition  0-58  grm.  Ft. 
In  100  parts, — 
Carbon  ....  38-57 
Hydrogen  . . . 4-05 
Nitrogen  . . . . 17-82 
Oxygen  ....  39-56 
• 100-00 
The  formula  C5  Hg  Nj  O4  requires, — 
Carbon  ...  5 60  37-97 
Hydrogen  . . 6 6 3-79 
Nitrogen  . . 2 28  17-72 
Oxygen  ...  4 64  40-52 
100-00 
This  compound  does  not  contain  any  water  of  crystallization.  In  order  to  determine 
the  oxalic  acid  contained  therein,  0-282  grm.  were  dissolved  in  water  and  precipitated 
with  chloride  of  calcium  and  a few  drops  of  ammonia.  The  weight  of  the  precipitate, 
after  conversion  into  carbonate  of  lime,  was  0-180  grm.  Since  100  parts  of  carbonate  of 
lime  correspond  to  90  parts  of  oxalic  acid,  Hg  O4,  0-180  grm.  of  Ca^  O,  COg  require 
0-162  grm.  C2H2O4.  Consequently  158  parts  of  binoxalate  of  glyoxahne  contain  90-7, 
or  one  equivalent  of  oxalic  acid,  and  for  one  equivalent  of  glyoxahne  is  left  C3  H4  N,. 
Glyoxaline,  C3H4N2. 
Chalk  is  added  to  a solution  of  binoxalate  of  glyoxaline,  and  the  mixture  warmed  till 
there  is  no  more  carbonic  acid  escaping.  The  filtrate  from  the  oxalate  of  lime  is  evapo- 
rated to  the  consistency  of  syrup,  and  left  to  stand  in  the  exsiccator  for  some  days. 
The  glyoxahne  crystahizes  only  -with  difficulty  in  prisms  radiating  from  one  centre.  It 
melts  easily,  evaporates  at  higher  temperatures  in  dense  white  fumes,  and  smells  like 
