250 
Action  of  Water  on  Lead. 
Am.  Jour.  Pharm> 
May,  1888. 
ACTION  OF  WATER  ON  LEAD.* 
By  M.  MtiLLER. 
A  sample  of  water  from  the  Ocker  was  distilled.  The  amounts  of 
dissolved  gases  and  of  ammonia  were  determined  in  the  first,  middle, 
and  last  fractions,  and  the  behavior  of  the  different  fractions  with  lead 
observed.  The  water  before  distillation  contained  0.00015  per  cent,  of 
ammonia. 
First  fraction. 
Middle  fraction. 
Last  fraction. 
0-00115  p.  c. 
0-0001  p.  c. 
0-00008  p.  c. 
Dissolved  gases 
reduced  to  0°  and  760  mm.  pressure. 
Carbonic  anhydride,  .    .    .  . 
Oxygen,  
Nitrogen  (diff.)  
2-04  vol.  p.  c. 
1-159 
0  269  " 
0-612 
1-196  vol.  p.  c 
•0-178 
0-316 
0-702 
0-77  vol.  p.  c. 
0.025 
0-232 
0-513 
The  first  fraction  scarcely  attacked  polished  strips  of  pure  lead^ 
which  became  slowly  covered  with  a  thin  deposit.  The  water  re- 
mained perfectly  clear.  The  middle  and  last  fractions  acted  very 
energetically,  the  lead  was  rapidly  corroded,  and  the  water  became 
turbid.  In  order  to  ascertain  whether  the  protecting  influence  of  the 
first  fraction  was  due  to  the  ammonia  or  the  carbonic  anhydride  it 
contained,  well  water,  perfectly  free  from  ammonia,  was  distilled,  and 
the  amount  of  gas  dissolved  in  different  portions  of  the  distillate  was 
ascertained. 
First  fraction. 
Middle  fraction. 
Last  fraction. 
Dissolved  gases  i 
Carbonic  anhydride,    .    .  . 
Nitrogen  (diff),  
educed  to  0°  anc 
2-661  vol.  p.  c. 
2-030 
0-198 
0-433 
760  mm.  pressu 
1-312  vol.  p.  c. 
0-218 
0-358 
0-738 
re. 
1.047  vol.  p.  c. 
0069 
0-341 
0-637  " 
In  this  case  also  the  first  fraction  showed  scarcely  any  action  on 
lead,  after  remaining  in  contact  with  it  for  24  hours.    The  middle  and 
^  J. pr.  Chem.  [2],  xxxvi,  317—340.   Reprinted  from  Jour.  Chem.  Soc,  1888,  p.  225. 
