Am.  Jour.  Pharm. 
Oct.,  1918. 
Determination  of  Morphine. 
701 
Comparing  this  with  the  titration  made  at  the  outset  of  the  exper- 
iment, the  loss  of  morphine  is  equivalent  to  0,26  Cc.  of  standard 
acid  or  0.0078  Gm.  of  base.  Since  the  extraction  by  chloroform- 
alcohol  is  quantitative,  this  is  loss  by  precipitation  from  solution  in 
5  Cc.  of  water  in  presence  of  5  Cc.  of  chloroform. 
Experiment.  12. — Precipitation  was  effected  in  the  presence  of 
water  only,  no  organic  solvent  being  employed.  Crystallized  mor-' 
phine  was  dissolved  in  2.0  Cc.  N  sulphuric  acid.  To  this  was  added 
8  Cc  of  fVV  N  ammonium  hydroxide.  The  precipitate  was  allowed 
to  form  while  standing  over  night.  The  remainder  of  the  manipula- 
tion resembled  that  in  Experiment  8,  but  distilled  water  was  used  to 
wash  the  precipitate. 
Titration  results : 
Experiment  13. — A  weighed  quantity  of  pure  crystallized  mor- 
phine was  shaken  and  allowed  to  stand  over  night  with  5  Cc.  of 
water  and  10  Cc.  of  well-washed  ether.  It  was  then  filtered,  with- 
out washing,  through  a  cotton  plug. 
The  undissolved  residue  was  titrated. 
Total  acid  used 
Acid  equivalent  to  the  alkali 
Acid  equivalent  to  the  morphine 
Weight  of  morphine  found 
Weight  of  morphine  originally  taken 
Loss  in  precipitation 
15.00  Cc. 
8.55  Cc. 
6.45  Cc. 
0.1935  Gm. 
0.2000  Gm. 
0.0065  Gm. 
Total  acid  used  =21.1  Cc. 
Acid  equivalent  to  the  alkali  =11.3  Cc. 
Acid  equivalent  to  the  morphine  =  9.8  Cc. 
The  filtrate  was  also  titrated. 
Total  acid  used  =  2.5  Cc. 
Acid  equivalent  to  the  alkali  =  2.3  Cc. 
Acid  equivalent  to  the  morphine  =  0.2  Cc. 
From  the  above  we  find 
Weight  of  morphine  undissolved  =  0.2940  Gm. 
Weight  of  morphine  dissolved     =  0.0060  Gm. 
Since  the  weight  of  morphine  originally  taken  was  0.3000  Gm.,  a 
perfect  balance  is  thus  established. 
