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प्रश्न
Explain why alkali and alkaline earth metals cannot be obtained by chemical reduction methods?
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उत्तर
In the process of chemical reduction, oxides of metals are reduced using a stronger reducing agent. Alkali metals and alkaline earth metals are among the strongest reducing agents and the reducing agents that are stronger than them are not available. Therefore, they cannot be obtained by chemical reduction of their oxides.
संबंधित प्रश्न
When an alkali metal dissolves in liquid ammonia the solution can acquire different colours. Explain the reasons for this type of colour change.
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Which of the alkali metal is having least melting point?
Which one of the following alkali metals gives hydrated salts?
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By adding gypsum to cement
Which of the following elements does not form hydride by direct heating with dihydrogen?
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(i) High boiling point.
(ii) High negative standard electrode potential.
(iii) High density.
(iv) Large atomic size.
Which of the following compounds are readily soluble in water?
(i) BeSO4
(ii) MgSO4
(iii) BaSO4
(iv) SrSO4
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The stability of peroxide and superoxide of alkali metals increase as we go down the group. Explain giving reason.
The valence shell electronic configuration of alkali metals is ______.
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Given below are two statements, one is labelled as Assertion (A) and the other is labelled as Reason (R).
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 :
Alkali metals are powerful reducing agents because ______.
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