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प्रश्न
The stability of peroxide and superoxide of alkali metals increase as we go down the group. Explain giving reason.
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उत्तर
As the size of metal ions increases, the stability of peroxides and superoxides increases. Peroxide and superoxide ions combine with a large size of alkali metals. Lithium forms monoxide, sodium forms peroxide and potassium, rubidium and caesium forms superoxide.
\[\ce{Li + O2 -> Li2O}\]
\[\ce{Na + O2 -> Na2O2}\]
\[\ce{K + O2 -> KO2}\]
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संबंधित प्रश्न
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Which of the following compounds are readily soluble in water?
(i) BeSO4
(ii) MgSO4
(iii) BaSO4
(iv) SrSO4
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(i) Beryllium is not readily attacked by acids because of the presence of an oxide film on the surface of the metal.
(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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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 correct order of hydration enthapies of alkali metal ions is ______.
The correct order of conductivity of ions in water is ______.
Alkali metals are powerful reducing agents because ______.
Which element from following is used as moderator in nuclear reactor?
