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प्रश्न
The alkali metals are low melting. Which of the following alkali metal is expected to melt if the room temperature rises to 30°C?
पर्याय
Na
K
Rb
Cs
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उत्तर
Cs
Explanation:
Among alkali metals, melting point decreases as the strength of metallic bonding decreases with increasing size of the atom. Thus, Cs has the lowest melting point (28.5°C) and will melt at 30°C.
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संबंधित प्रश्न
Why are alkali metals not found in nature?
Explain why alkali and alkaline earth metals cannot be obtained by chemical reduction methods?
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Metals form basic hydroxides. Which of the following metal hydroxide is the least basic?
The solubility of metal halides depends on their nature, lattice enthalpy and hydration enthalpy of the individual ions. Amongst fluorides of alkali metals, the lowest solubility of LiF in water is due to ______.
Which of the following compounds are readily soluble in water?
(i) BeSO4
(ii) MgSO4
(iii) BaSO4
(iv) SrSO4
Choose the correct statements from the following.
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(ii) Beryllium sulphate is readily soluble in water as the greater hydration enthalpy of Be2+ overcomes the lattice enthalpy factor.
(iii) Beryllium exhibits coordination number more than four.
(iv) Beryllium oxide is purely acidic in nature.
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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:
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Assertion (A) : Lithium salts are hydrated.
Reason (R) : Lithium has higher polarising power than other alkali metal group members.
In the light of the above statements, choose the most appropriate answer from the options given below :
