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प्रश्न
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.
उत्तर
(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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संबंधित प्रश्न
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The ease of absorption of the hydrated alkali metals ions in an ion-exchange resin follows the order:
Match List-I with List-II.
| List-I | List-II |
| (Metal) | (Emitted light wavelength (nm)) |
| (a) Li | (I) 780.0 |
| (b) Na | (II) 455.5 |
| (c) Rb | (III) 670.8 |
| (d) Cs | (IV) 589.2 |
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Reason (R) : Lithium has higher polarising power than other alkali metal group members.
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