Lithium

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Lithium is an alkali metal with an atomic weight of 6.941. Lithium has a melting point of 356.97 °F, and a boiling point of 2448 °F. Lithium is the lightest of the metallic elements, has a silver color, and has corrosive characteristics. Common uses for lithium include: heat transfer purposes, mixed with carbonates to create medications for manic-depressive disorders, as a reagent for organic chemistry reactions, as a high temperature lubricant when mixed with oils, and as a mix with other metallic alloys for aircraft construction.

The isolation of lithium is not normally performed in a laboratory. Commercial scale amounts of lithium are isolated electrolytically from ore which contains lithium.

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Spodumene, the ore with the formula LiAl(SiO3)2, is most frequently used for lithium isolation. The alpha form of the ore is heated to 2012 °F into the soft beta ore form. Heated sulphuric acid is mixed with the beta ore, extracted through water, and the end result is a solution of lithium sulphate. Sodium carbonate is used to wash the solution and form a precipitate of insoluble lithium carbonate. The precipitate is reacted with two parts of hydrochloric acid to yield two parts of lithium chloride, carbon dioxide, and water. The lithium chloride, which has a melting point of greater than 1112 °F, is mixed with potassium chloride to decrease the melting point required for the final electrolysis step to around 806 °F; decreasing the melting point means that less energy is required for the electrolysis process. The electrolysis step separates the positive cathode lithium from the negative anode chloride to yield pure lithium.