Chemical elements
  Lithium
    Isotopes
    Energy
    Production
    Application
    Physical Properties
    Chemical Properties
      Lithium hydride
      Lithium chloride
      Lithium bromide
      Lithium iodide
      Lithium iodide tetrachloride
      Lithium hypochlorite
      Lithium chlorate
      Lithium perchlorate
      Lithium bromate
      Lithium iodate
      Lithium periodates
      Lithium monoxide
      Lithium peroxide
      Lithium hydroxide
      Lithium monosulphide
      Lithium polysulphides
      Lithium sulphite
      Lithium sulphate
      Lithium persulphate
      Lithium thiosulphate
      Lithium dithionate
      Lithium selenide
      Lithium selenite
      Lithium selenate
      Lithium chromate
      Lithium permanganate
      Lithium molybdates
      Lithium nitride
      Lithium hydrazoate
      Lithamide
      Lithium nitrite
      Lithium nitrate
      Lithium phosphide
      Lithium orthophosphate
      Lithium pyrophosphate
      Lithium metaphosphate
      Lithium arsenide
      Lithium meta-arsenite
      Lithium arsenate
      Lithium antimonide
      Lithium antimonate
      Lithium carbide
      Lithium carbonate
      Lithium percarbonate
      Lithium cyanide
      Lithium thiocyanate
      Lithium silicide
      Lithium silicates
      Lithium borates

Lithium carbonate, Li2CO3






The Lithium carbonate, Li2CO3 is prepared by boiling a solution of a lithium salt with ammonium, sodium, or potassium carbonate, its slight solubility inducing crystallization and facilitating purification. A process for its manufacture from lepidolite has also been devised.

The melting-point of the carbonate is given as 618° C. (Ramsay and Eumorfopoulos), 695° to 699° C. (Carnelley), and 710° C. (Le Chatelier). Its boiling-point is 1200° C., and its density is 2.111. The number of grams of lithium carbonate which dissolve in 100 grams of water at various temperatures is given in the following table, after Bewad -

Temperature, °C 010203040506080100
Grams Li2CO3 in 100 g. H2O. 1.541.251.431.331.171.081.010.850.72


Rothmund gives the solubility at 25° C. as 0.1687 gram-molecules per litre. According to Tschugajev and Chlopin, 100 grams of the saturated solution at 75° C. contain 0.833 gram of the salt, and at 95° C. 0.723 gram. With the exception of the phosphate and fluoride, the carbonate is the most insoluble salt of lithium. The solubility is considerably increased by the presence of carbon dioxide, a solution of lithium hydrogen carbonate being formed. On evaporation of the solution the carbon dioxide is expelled, so that the primary carbonate is decomposed and has not been isolated. Geffcken has studied the influence of other salts on the solubility of the normal carbonate. According to Bewad, the density of the saturated solution at 0° C. is 1.017, and at 15° C. it is 1.014.

When heated below 1000° C. lithium carbonate undergoes partial decomposition into the oxide and carbon dioxide, a resemblance to calcium, but a distinction from sodium and potassium -

Li2CO3=Li2O+CO2.

The dissociation-pressure has been investigated by Johnston. Heating with charcoal yields the monoxide, sodium carbonate being reduced to the metal by similar treatment. At the temperature of the electric furnace excess of charcoal produces the carbide, an example of the relationship between lithium and calcium.

The heat of formation of the normal carbonate and that of the primary carbonate have been calculated by Muller -

2LiOH,Aq. + CO2,Aq.=Li2CO3,Aq. + 20.4 Cal.;
2LiOH,Aq.+2CO2,Aq.=2LiHCO3,Aq.+22.l Cal.

For the heat of formation of the solid normal carbonate de Forcrand gives the equationsLi2O,Aq.+(CO2)=[Li2CO3]+54.23 Cal.;
2[Li]+(O)+(CO2)=[Li2CO3]+44.20 Cal.

Basic carbonates have been described by Fllickiger, and a double salt with potassium by Le Chatelier.


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