question_answer 59)

    Metallic elements are described by their standard electrode potential, fusion enthalpy, atomic size, etc. The alkali metals are characterised by which of the following properties? (a) High boiling point                                                      (b) High negative standard electrode potential (c) High density                                                                 (d) Large atomic size

Answer:

  (b, d) Alkali metals possess high negative electrode potentials and large atomic size \[\underset{{{E}^{{}^\circ }}}{\overset{{}}{\mathop{{}}}}\,\,\,\,\,\,\,\underset{-3.04}{\mathop{Li}}\,\,\,\,\underset{-2.71}{\mathop{Na}}\,\,\,\underset{-2.93}{\mathop{\,K}}\,\,\,\,\underset{-2.93}{\mathop{Rb}}\,\,\,\,\underset{-2.92}{\mathop{Cs}}\,\] Act as strong reducing agents. \[\underset{At.radii\,(pm)}{\overset{{}}{\mathop{{}}}}\,\,\,\,\,\,\,\underset{152}{\mathop{Li}}\,\,\,\,\underset{186}{\mathop{Na}}\,\,\,\underset{227}{\mathop{\,K}}\,\,\,\,\underset{248}{\mathop{Rb}}\,\,\,\,\underset{265}{\mathop{Cs}}\,\]