698  Determination  of  Morphine.        { Am,^\^garm' 
Extraction  of  Morphine  Salts  by  a  Mixture  of  Chloroform  and 
Alcohol.  Experiment  7. — Crystallized  morphine  (0.3000  Gm.)  was 
dissolved  in  dilute  sulphuric  acid,  The  solution  was  made  alkaline 
by  sodium  hydroxide,  then  faintly  acid  with  hydrochloric  acid.  This 
acid  mixture  was  then  extracted  four  times  with  chloroform-alcohol 
exactly  as  were  the  alkaline  solutions  in  Experiments  5  and  6.  The 
extracts  wTere  combined,  the  chloroform  and  alcohol  distilled  on  a 
water  bath  and  the  residue  set  aside  for  further  examination. 
The  acid  aqueous  layer  was  made  slightly  alkaline  with  sodium 
hydrogen  carbonate  and  again  extracted  four  times  with  the  same 
solvent  as  before.  The  residue  from  these  extractions  was  set  aside 
for  further  examination. 
Acid  Extract. — This  dissolved  almost  completely  in  water,  leav- 
ing only  a  slight  oily  cloud  of  insoluble  matter  (chloroform?).  The 
solution  was  acidified  with  standard  acid  and  titrated  with  sodium 
hydroxide. 
Total  acid  added  =  5.00  Cc. 
Acid  equivalent  to  the  alkali  used  =  5.15  Cc. 
A  trace  of  free  acid  (=0.15  Cc.  -f^)  was  therefore  contained  in  the 
extract. 
After  titration,  the  lacmoid  was  precipitated  by  adding  a  little 
slaked  lime.  The  solution  was  filtered,  acidified,  and  tested  with 
decinormal  iodine  solution.  The  formation  of  a  characteristic  pre- 
cipitate demonstrated  the  presence  of  morphine. 
Alkaline  Extract. — This  was  dissolved  in  a  known  amount  of 
standard  sulphuric  acid.  The  solution  was  titrated  with  standard 
sodium  hydroxide. 
Total  acid  used  =  15.3  Cc. 
Acid  equivalent  to  the  alkali  =  6.4  Cc. 
Acid  equivalent  to  the  morphine  =  8.9  Cc. 
The  morphine  extracted  from  the  alkaline  solution  was  therefore 
0.2670  Gm.,  so  that  0.0330  Gm.  must  have  been  extracted  from  the 
acid  solution  in  the  form  of  a  salt  by  the  chloroform-alcohol  mixture. 
Precipitation  of  Morphine  by  Ammonium'  Hydroxide  under 
Various  Conditions.  Experiment  8. — Crystallized  morphine  was 
weighed  into  a  stoppered  flask  and  dissolved  in  25  Cc.  of  -ft  sul- 
phuric acid.    To  this  was  added  8  Cc.  of  alcohol,  20  Cc.  of  ether 
