AmjS?M>86arm'}      Solubility  of  Carbonate  of  Lithium.  347 
THE  SOLUBILITY  OF  CARBONATE  OF  LITHIUM  IN 
WATER  CONTAINING  CARBONIC  ACID. 
By  A.  Goldammee. 
It  is  known  that  the  carbonates  of  the  alkaline  earths,  though 
nearly  insoluble  in  water,  are  soluble  to  a  considerable  degree  in 
water  containing  carbonic  acid,  and  that  in  this  respect  lithium  re- 
sembles them  in  behavior.  Lithium,  it  is  true,  is  soluble  in  water, 
and  I  have  obtained  results  corresponding  with  Bewad's  statement 
that  one  part  is  soluble  in  75  parts  of  water  at  15°  C;  but,  its  solu- 
bility is  considerably  increased  by  the  introduction  of  carbonic  acid. 
This  behavior  of  lithium  carbonate  has  found  only  slight  mention  in 
technical  literature,  but  it  presents  some  interest  in  respect  to  the 
alleged  existence  of  a  solid  bicarbonate  of  lithium. 
In  an  experiment  in  which  I  suspended  75  gm.  of  finely  powdered 
lithium  carbonate  in  a  litre  of  water  and  passed  a  current  of  carbonic 
acid  through  it  during  three  days  5*41  per  cent,  by  weight  of  lithium 
carbonate  went  into  solution.  When  atmospheric  pressure  was  used 
the  solution  was  effected  much  more  rapidly.  In  experiments  where 
a  pressure  of  four  atmospheres  was  used  during  six  hours,  in  one  case 
6'40  per  cent,  and  in  another  6*87  per  cent,  of  lithium  carbonate 
was  dissolved.  It  is  assumed  that  under  greater  pressure,  continued 
during  a  longer  time,  the  carbonic  acid  would  have  effected  the  solu- 
tion of  still  more  lithium ;  but  from  the  solution  prepared  under  the 
above-mentioned  pressure  the  lithium  carbonate  separated  out  in  a 
crystalline  form  immediately  after  filtration,  whilst  a  solution  pre- 
pared without  pressure  remained  unaltered  during  several  days,  and, 
under  proper  conditions,  a  longer  time. 
It  would  be  of  advantage  to  the  mineral  water  manufacturer  if  a 
solution  of  the  bicarbonate  of  lithium  could  be  kept  unaltered ;  it 
would  present  many  conveniences,  seeing  the  difficult  solubility  of 
the  monocarbonate.  This,  according  to  my  experience,  however,  is 
only  possible  by  maintaining  the  solution  under  pressure  in  a  manner 
analogous  to  a  solution  of  magnesium  bicarbonate.  A  solution  con- 
taining 5  per  cent,  of  lithium  monocarbonate  will,  it  is  true,  remain 
unaltered  for  a  long  time,  in  bottles  filled  to  the  cork;  but,  after  the 
removal  of  a  part  of  the  contents  of  the  bottle,  as  well  as  after  several 
openings  of  the  cork,  and  especially  upon  a  rise  of  temperature,  a 
considerable  quantity  of  lithium  carbonate  crystallizes  out.     If  a 
