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On combustion Li, Na and K in excess of air, the major oxides formed, respectively, are-

1. Li2O2, Na2O2 and K2O2
2. Li2O, Na2O2 and K2O
3. Li2O, Na2O2 and KO2
4. Li2O, Na2O and K2O2

Correct answer: Li2O, Na2O2 and KO2

Solution

Lithium primarily forms lithium oxide (Li2O) due to its lower reactivity, while sodium reacts to form sodium peroxide (Na2O2) in excess oxygen. Potassium, being more reactive, forms potassium superoxide (KO2) under similar conditions, making option C the correct choice.

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