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प्रश्न
When heated in air, the alkali metals form various oxides. Mention the oxides formed by Li, Na and K.
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उत्तर
Alkali metals forms oxide when reacted with air. Lithium forms monoxide, sodium forms peroxide and potassium forms superoxide.
\[\ce{4Li + O2 -> 2Li2O}\]
\[\ce{Na + O2 -> Na2O2}\]
\[\ce{L + O2 -> KO2}\]
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संबंधित प्रश्न
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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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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:
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