The Foundations of Chemistry

USES OF GROUP IA METALS AND THEIR COMPOUNDS

Lithium, Li

Metallic lithium has the highest heat capacity of any element. It is used as a heat transfer

medium in experimental nuclear reactors. Extremely lightweight lithium–aluminum alloys

are used in aircraft construction. Lithium compounds are used in some lightweight dry

cells and storage batteries because they have very long lives, even in extreme tempera-

tures. LiCl and LiBr are very hygroscopic and are used in industrial drying processes and

air conditioning. Lithium compounds are used for the treatment of some types of mental

disorders (mainly manic depression).

Sodium, Na

Sodium is by far the most widely used alkali metal because it is so abundant. Its salts are

essential for life. The metal itself is used as a reducing agent in the manufacture of drugs

and dyes and in the metallurgy of such metals as titanium and zirconium.

heat

TiCl 4 (g)
4Na(
)888n4NaCl(s)
Ti(s)

Highway lamps often incorporate Na arcs, which produce a bright yellow glow. A few

examples of the uses of sodium compounds are NaOH, called caustic soda, lye, or soda

lye (used for production of rayon, cleansers, textiles, soap, paper, and many polymers);

Na 2 CO 3 , called soda or soda ash, and Na 2 CO 3 10H 2 O, called washing soda (also used

as a substitute for NaOH when a weaker base is acceptable); NaHCO 3 , called baking soda

23-3

924 CHAPTER 23: Metals II: Properties and Reactions

The yellowish glow of some highway
lamps is due to a sodium arc.
Mercury lamps give a bluish glow.

Spacings of energy levels are different for different alkali metals. The salts of the alkali

metals impart characteristic colors to flames: lithium (red), sodium (yellow), and potassium

(violet).

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The highly corrosive nature of both
lithium and sodium is a major
drawback to applications of the
pure metals.