Physical properties of the alkali

The Group 1 elements are soft, low-melting metals which crystallize with bee lattices. All are silvery-white except caesium which is golden yellow "- in fact, caesium is one of only three metallic elements which are intensely coloured, the other two being copper and gold (see also pp. 112, 1177, 1232). Lithium is harder than sodium but softer than lead. Atomic properties are summarized in Table 4.1 and general physical properties are in Table 4.2. Further physical properties of the alkali metals, together with a review of the chemical properties and industrial applications of the metals in the molten state are in ref. 11. 

Main atomic and physical properties of the alkali earth metals are summarized in Tables 5.7 and 5.8. Their typical electron configurations correspond to the outermost ns2 electrons. Alkali earth metals show relatively low 1st and 2nd ionization energies this can be related to the fact that almost without exception both the external 5 electrons take part together in bond formation whether the bond is ionic or covalent. 

Foerster and Kubel, Zeitsch. anorg. Chern., 1924, 139, 261. For various physical properties of the alkali sulphites and hydrogen sulphites, see Lewis and Rivett, Trams. Chem.Soc., 1924,125,1156,1162 Foerster,BroscheandNorborg-Schulz,Zeitsch.physikal. Ghem., 1924, no, 435 Sabalitschka and Kubisch, Arch. Pham., 1924, 262, 105 Schiller and Wilhelm, Zeitsch. angew, Chem., 1919, 32, 198. 

Physical properties of the alkali melal hydrides are given in Table I. Sodium hydride finds commercial usage in organic synthesis in condensation and alkylation reactions. 

Fundamental atomic and physical properties of the alkali metals are given in Tables 1, 2, and 3. The elements are characterized by having electron configurations each with a single s orbital electron outside a noble gas core (see Table 1). Sodium and cesium are mononucUdic so that their relative atomic masses are known extremely accurately in effect, the same can be written for potassium and rubidium since their isotopes (of which there are three and two, respectively) have... 

TABLE 18.4 Selected Physical Properties of the Alkali Metals... 

Some of the physical properties of the alkali metals are listed in Table 3. All these elements are so soft that they can be easily cut with a knife. The freshly cut surface of an alkali metal is shiny, but it dulls quickly as the metal reacts with oxygen and water in the air. Like other metals, the alkali metals are good conductors of electricity. 

Table I. Physical Properties of the Alkali Carbonate Eutectic Melt...

Table 10.1 Some physical properties of the alkali metals, M, and their ions,...

Correlate atomic properties, such as ionization energy, with electron configuration, and explain how these relate to the chemical reactivity and physical properties of the alkali and alkaline earth metals (groups lA and 2A). (Section 7.7)... 

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