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प्रश्न
Which one of the following alkali metals gives hydrated salts?
विकल्प
Li
Na
K
Cs
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उत्तर
Li
Explanation:
The smaller the size of an ion, the more highly is it hydrated. Among the given alkali metals, Li is the smallest in size. Also, it has the highest charge density and highest polarising power. Hence, it attracts water molecules more strongly than the other alkali metals. As a result, it forms hydrated salts such as
LiCl.2 H2O. The other alkali metals are larger than Li and have weaker charge densities. Hence, they usually do not form hydrated salts
संबंधित प्रश्न
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Write a balanced equation for the reaction between KO2 and water.
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By adding gypsum to cement
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(iii) Beryllium exhibits coordination number more than four.
(iv) Beryllium oxide is purely acidic in nature.
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When a metal of group 1 was dissolved in liquid ammonia, the following observations were obtained:
(i) Blue solution was obtained initially.
(ii) On concentrating the solution, blue colour changed to bronze colour.
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The valence shell electronic configuration of alkali metals is ______.
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Match List-I with List-II.
| List-I | List-II |
| (Metal) | (Application) |
| (a) Cs | (I) High temperature thermometer |
| (b) Ga | (II) Water repellent sprays |
| (c) B | (III) Photoelectric cells |
| (d) Si | (IV) Bullet proof vest |
Choose the most appropriate answer from the options given below:
The metal mainly used in devising photoelectric cells is ______.
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