128 
Explosive  Mixture,  etc. 
j  Am.  Joxte.  Phajrwv. 
t     Mar.  1,  187S, 
The  residue,  consisting  of  the  paraffin,  is  then  weighed,  and  the  stea- 
ric acid  is  estimated  by  difference. — Chem.  Neivs,  Lo?id.,  Jan.  10*, 
1873. 
EXPLOSIVE  MIXTURE  OF  NITRATE  OF  POTASH  AND  AC  ES- 
TATE OF  SODA* 
By  M.  Yiolette. 
An  accident  in  the  author's  laboratory  made  known  to  him  a  sin- 
gular reaction  between  nitrate  of  potash  and  acetate  of  soda,  which,, 
under  the  influence  of  heat,  constitutes  an  explosive  mixture  equal  m 
force  to  gunpowder.  In  some  researches  upon  saltpetre  he  had  heated 
moderately  in  a  small  phial  a  few  grams  each  of  nitrate  of  soda  and 
acetate  of  soda,  both  previously  fused  and  anhydrous.  The  two  salts-; 
melted  formed  a  colorless  and  transparent  liquid,  which  gave  off  a  few 
gaseous  bubbles.  At  the  same  moment,  a  violent  explosion  occurred*., 
accompanied  by  flame  and  smoke,  which  scattered  the  phial  in  frag- 
ments all  over  the  laboratory  ;  a  fresh  gaseous  combination  between, 
the  elements  of  the  salts  had  taken  place,  leaving  a  slight  residue  of 
alkaline  carbonate. 
In  repeating  the  experiment  a  gram  of  nitrate  of  potash  was  melted! 
in  a  small  platinum  capsule  at  a  gentle  heat,  and  a  gram  of  acetate  o-f' 
soda  previously  fused  added  to  it.  At  a  temperature  of  about  300a 
0  the  mixture  remained  fluid,  transparent  and  without  alteration  m< 
long  as  the  temperature  remained  constant  ;  upon  raising  it  to  about 
850°  C.  there  was  a  slight  ebullition  followed  instantly  by  a  loud  ex- 
plosion, with  light  and  smoke,  similar  to  that  of  gunpowder.  As  be- 
fore,  there  was  a  slight  residue  of  alkaline  carbonates.  The  same  re- 
sult followed  when  a  substance  in  ignition  without  flame  was  plunged 
into  the  liquid  at  300°  C. 
If  the  melted  mixture  be  poured  upon  a  cold  surface  a  white  sub- 
stance is  obtained,  which  is  hard,  brittle,  rather  hygroscopic^  more 
fusible  than  nitrate  of  potash,  and  being  melted  explodes  violently, 
In  the  solid  form  it  does  not  burn  when  placed  in  contact  with  an  ig- 
nited body  ;  but  reduced  to  fine  powder,  it  deflagrates  violently  uposii 
the  application  of  a  flame. 
The  explosive  properties  of  the  mixture  are  only  developed  when 
the  nitrate  of  potash  and  acetate  of  soda  are  present  in  certain  pro- 
*  Journal  do  Pharmacie  et  de  Chimie,  xvi,  333. 
