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Question
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?
(i) High boiling point.
(ii) High negative standard electrode potential.
(iii) High density.
(iv) Large atomic size.
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Solution
(ii) High negative standard electrode potential.
(iv) Large atomic size.
Explanation:
Alkali metals have larger atomic size and low density. These metals lose electrons due to less effective nuclear charge. They have a high value of electrode potential.
Lithium has the highest negative reduction potential value. Due to the small size of lithium it has a small atomic size and highest ionization enthalpy.
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