76 
LITHIUM  AND  ITS  SALTS. 
its  atomic,  or  uniting  proportion  does  not  exceed  seven  on  the 
hydrogen  scale. 
Oxide  of  Lithia, — Lithia  is  separated  from  powdered  tri- 
phyllin,  the  most  abundant  mineral  containing  it,  by  digestion 
to  solution  in  hydrochloric  acid,  and  peroxidizing  the  iron 
with  a  little  nitric  acid.  Dilute  the  liquid  with  water,  and  then 
add  an  excess  of  ammonia  to  precipitate  the  phosphoric  acid 
and  sesquioxide  of  iron.  Through  the  ammoniacal  solution 
pass  sulphuretted  hydrogen,  to  separate  magnesia,  filter,  evap- 
orate to  dryness,  calcine  the  residue  to  expel  ammoniacal  salts, 
and  dissolve  the  chloride  of  lithium  in  alcohol.  Upon  the 
addition  of  an  excess  of  carbonate  of  ammonia,  a  carbonate  of 
lithia  precipitates  after  a  time,  and  must  be  collected  on  a  filter, 
and  washed  with  alcohol  of  0.80  per  cent.  Thij  carbonate, 
when  finally  powdered  and  boiled  in  a  large  quantity  of  water^ 
becomes  dissolved,  and  upon  the  addition  of  lime  is  decarbon- 
ated. The  filtered  solution,  upon  evaporation,  yields  hydrated 
oxide  of  lithia. — (BootL)^ 
This  preparation  is  insoluble,  or,  at  least,  nearly  so,  and  re- 
mains unaltered  by  all  external  actions.  It  possesses  a  dis- 
agreeable caustic  taste ;  it  is  reactionary  alkali,  and  readily 
attacks  platinum. 
Chloride  of  Lithium  appears  in  crystallized  cakes,  and  is 
soluble  in  alcohol  and  water.  Unlike  oxide  of  lithia,  it  is  de- 
liquescent on  exposure. 
Sidphuret  of  Lithium  is  soluble  in  water  and  alcohol,  and 
eminently  pyrophoric. 
Sulphate  of  Lithia  exists  as  a  crystallized  body,  and  remains 
unalterable  by  exposure.  Its  formula  is  LiO,S02.  It  is 
soluble  in  water,  and  nearly  insoluble  in  alcohol.  With  sul- 
phate of  soda  it  forms  a  double  salt,  NaO,S03+LiO,S03+6,HO. 
Phosphate  of  Lithia  The  neutral  phosphate  of  this  base, 
SLiOjPOg  is  almost  insoluble.  The  bi.phosphate,  LiO,POr 
is  very  soluble  in  water,  and  crystallizable.  With  phosphate  of 
soda  it  forms  a  double  salt,  soluble  in  1400  parts  of  water  at 
59°,  and  in  950  parts  at  210*^.  It  is  insoluble  in  all  liquids 
containing  phosphate.  It  is  a  white  powder  and  has  for  itv^ 
formulge  2NaO,P05H-2LiO,P05. 
