354  On  Determination  of  Acetanilid.      {A^udT  ST™' 
This  was  washed  with  water  and  dried.  It  had  an  acid  reaction 
and  was  soluble  in  alkalies,  neutralizing  it.  As  it  was  derived  from 
Kalmeghin  the  name  Kalmeghic  acid  was  given  to  it. 
0.043  Gm.  gave  0.0699  Gm.  of  H20  and  0.2053  Gm.  of  CO.. 
Hence  C  75.23  H  10.4. 
The  formula  is  C14H2302. 
This  acid,  as  well  as  the  bitter  principle  (b),  gave  fluorescein 
test,  showing  the  presence  of  a  benzine  nucleus  with  two  adjacent 
side  chains. 
Chemical  Laboratory,  Presidency  College,  Bengal. 
ON  THE  DETERMINATION  OF  ACETANILID. 
By  Dr.  A.  Mirkin,  Cincinnati,  Ohio. 
The  determination  of  acetanilid  in  tablets  is  still  effected  by  an 
extraction  with  chloroform,  the  chloroform  being  collected  in  a 
tared  flask,  evaporated,  and  the  residue  dried  at  a  low  temperature 
and  weighed.  This  method  frequently  gives  low  results  on  account 
of  the  volatility  of  acetanilid,  and  very  often  it  is  not  applicable  at  all 
on  account  of  the  presence  of  other  ingredients  in  the  tablets  which 
are  also  soluble  in  chloroform. 
The  volumetric  method  adopted  by  the  Association  of  Official 
Agricultural  Chemists,  in  which  a  solution  of  potassium  bromide- 
bromate  is  used,  does  not  always  give  accurate  results,  and  it  seemed 
desirable  to  find  another  method  which  might  prove  successful  when 
other  methods  failed. 
Bay  and  Vignon  (Comptes  Rend.,  135,  507;  Centralblatt,  1902, 
ii,  1094)  determine  nitrous  acid  by  titrating  with  a  standard  solution 
of  aniline.  The  nitrous  acid  is  used  up  in  diazotizing  the  aniline. 
As  soon  as  the  nitrous  acid  is  gone  a  piece  of  potassium  iodide-starch 
paper,  with  which  the  solution  is  tested  from  time  to  time,  does  not 
turn  blue  any  more.  This  reaction  is  reversible,  and  one  can  titrate 
aniline  with  a  standardized  solution  of  sodium  nitrite.  By  convert- 
ing acetanilid  into  aniline  and  titrating  with  a  standard  sodium  nitrite 
solution,  we  have  a  quick  method  of  determination.  In  order  to 
obtain  correct  results  all  the  conditions  mentioned  below  must  be 
strictly  adhered  to. 
