94 
Aceto-Nitrate  of  Iron, 
(  Am.  Jour.  Pharm. 
t      Feb.,  1879. 
Now,  in  the  course  of  the  experiments  I  am  about  to  describe  various 
salts,  having  different  tints  of  color,  some  being  nearly  black  and  having 
various  degress  of  deliquescence,  have  doubtless  been  obtained,  and 
may  very  probably  be  the  salts  having  the  various  composition  attributed 
to  them  by  Mr.  Kestner,  and  I  must  admit  that  no  attempt  to  analyze 
them  has  as  yet  been  made  by  me.  But,  upon  recrystallization,  the 
various  salts  all  appeared  to  yield  one  and  the  same  salt  as  the  final 
product,  and  this  leads  me  to  suspect  that  the  various  salts  named  may 
in  reality  be  one  in  a  more  or  less  impure  condition.  Of  course,  I 
should  be  very  sorry  to  express  a  positive  opinion  upon  this  matter  with- 
out making  many  more  experiments  and  analyses,  and  it  is  proper  I 
hould  mention  that  the  experiments  we  have  in  hand  are  at  present  in 
a  very  unfinished  state.  Still,  I  am  bound  to  repeat  that,  as  far  as  I 
can  judge  with  my  present  knowledge,  we  appear  always  to  obtain  one 
definite  salt  by  the  recrystallization  of  any  of  the  others. 
Perhaps  the  best  mode  of  forming  the  acetonitrate  of  iron  is  to  dis- 
solve bydrated  ferric  oxide,  which  must  be  quite  recent  and  well 
washed,  in  a  mixture  of  glacial  acetic  and  nitric  acids,  in  which  the 
acetic  acid  is  in  considerable  excess  (say  two  or  three  parts  to  one); 
the  hydrated  oxide  contains  sufficient  water  to  dilute  the  solution,  and 
the  oxide  must  be  added  slowly  so  as  to  avoid  very  great  elevation  01 
temperature.  The  solution  so  formed  in  24  hours  deposits  a  quantity 
of  the  double  salt,  in  hard,  well-formed  crystals.  These,  drained  from 
the  mother-liquor  can  be  dissolved  in  a  small  quantity  of  warm  (not 
boiling)  water,  strained  if  necessary,  and  allowed  to  crystallize.  The 
crystals  so  deposited  have  all  the  characters  assigned  to  the  tetracetodi- 
aitrate  of  iron,  and  I  assume  may  be  fairly  taken  as  being  represented 
by  the  formula  given  for  that  compound. 
I  find  these  crystals  are  not  by  any  means  so  easily  decomposed  as 
the  original  description  would  lead  one  to  infer  ;  on  the  contrary,  they 
•ire  quite  permanent,  and  so  slightly  deliquescent  that  they  can  readily 
be  kept  in  paper  for  several  days  without  spoiling. 
They  are  very  soluble  in  water,  in  the  cold  or  gently  warmed,  but  1 
find  the  solution  of  the  salt  is  decomposed  by  boiling,  basic  compounds 
being  deposited  which  cannot  afterwards  be  got  into  solution.  It  is 
also  freely  soluble  in  alcohol,  but  practically  insoluble  in  ether. 
The  various  solutions  of  this  salt  have  a  pure  styptic  taste,  quite  free 
