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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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By adding gypsum to cement
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(ii) High negative standard electrode potential.
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(iv) Large atomic size.
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The valence shell electronic configuration of alkali metals is ______.
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 ______.
KO2 (potassium super oxide) is used in oxygen cylinders in space and submarines because it ______.
