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प्रश्न
The order of decreasing ionisation enthalpy in alkali metals is ______.
विकल्प
Na > Li > K > Rb
Rb < Na < K < Li
Li > Na > K > Rb
K < Li < Na < Rb
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उत्तर
The order of decreasing ionisation enthalpy in alkali metals is Li > Na > K > Rb.
Explanation:
On moving down the group as the size increases, the nuclear charge attraction decreases. The effect of increasing size outweighs the increasing nuclear charge. Thus, ionization enthalpy decreases. The order of decreasing ionization enthalpy is Li > Na > K > Rb
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संबंधित प्रश्न
What are the common chemical features of alkali metals?
Write a balanced equation for the reaction between Na2O and CO2.
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The alkali metals are low melting. Which of the following alkali metal is expected to melt if the room temperature rises to 30°C?
Which of the following elements does not form hydride by direct heating with dihydrogen?
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.
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(iv) Large atomic size.
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(i) BeSO4
(ii) MgSO4
(iii) BaSO4
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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 |
Choose the most appropriate answer from the options given below:
The metal mainly used in devising photoelectric cells is ______.
The correct order of hydration enthapies of alkali metal ions is ______.
The correct order of conductivity of ions in water is ______.
