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Question
When heated in air, the alkali metals form various oxides. Mention the oxides formed by Li, Na and K.
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Solution
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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