PREPARATION  OF  THE  DEUTOXIDE  OF  LEAD.  841 
be  regarded  as  non-essential,  it  appears  that  the  compound  con- 
sists entirely  of  sulphur  and  antimony. — Ohem.  Graz.y  March  15, 
1856,  from  Polyteehn.  Centratbl,  1855,  p.  1451. 
PREPARATION  OF  THE  DEUTOXIDE  OF  LEAD. 
In  the  Annalen  d.  Chemie  und  Pharmacie,  xiv.  383,  Professor 
Woehler  recommends  the  following  process  for  preparing  this 
deutoxide: 
A  solution  of  acetate  of  lead  is  precipitated  by  carbonate  of 
soda  and  a  current  of  chlorine  passed  through  the  mass  until  all 
the  carbonate  of  lead  has  been  converted  into  the  dark  brown 
deutoxide,  which  is  then  to  be  thrown  on  a  filter  and  washed. 
By  operating  in  this  way  all  the  lead  is  obtained  as  deutoxide, 
free  from  chloride  :  but  chloride  of  sodium  is  formed,  and  car- 
bonic and  acetic  acids  set  free.  The  two  salts  may  be  taken  in 
the  proportion  of  their  weights  of  equivalents,  but  it  is  better  to 
take  the  carbonate  of  soda  in  slight  excess,  in  order  to  more  ef- 
fectually guard  against  the  formation  of  chloride  of  lead.  Four 
parts  of  acetate  of  lead  gives  2i  p,  of  deutoxide,  while  only  1| 
parts  will  be  obtained  from  4  p.  of  minimum.  This  deutoxide 
instantly  becomes  white  in  sulphurous  acid  gas. 
Dr.  A.  Overbeck  (Archiv  d.  Pharm.  1856,  5)  recommends  the 
following  method  as  simple  and  economical : 
A  concentrated  solution  of  329.6  parts  of  red  cyanuret  of  po- 
tassium and  iron  is  boiled  with  47.2  p.  of.  potassa  and  112  p.  of 
protoxide  of  lead  in  its  hydrated  state,  until  the  solution  has  as- 
sumed the  well  known  color  of  (yellow)  ferrocyanuret  of  potas- 
sium ;  the  deutoxide  is  filtered,  washed  and  dried,  and  the  filtrate 
and  washings  evaporated  to  obtain  the  ferrocyanuret  of  potas- 
sium ;  the  yield  will  be  368.8  p.  of  the  latter,  and  120  p.  of 
the  deutoxide.  The  process  may  be  explained  as  follows  : — 
KO+PbO+K3Fe2Cy6=Pb02+2  (K2FeCy3).  This  deutoxide  is 
readily  heated  to  redness  in  sulphurous  acid  gas,  and  afterwards 
forms  a  purely  white  mass. 
A  deutoxide  prepared  by  Woehler's  process  was  found  by  Muck 
to  contain  1.54  per  cent,  chlorine,  equivalent  to  6.03  p.  c. 
chloride  of  lead ;  he  also  could  not  obtain  Crum's  test  for 
manganese  with  this  deutoxide  (Wittstein's  Vierteljahrsschr.  iv* 
