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JEE Main20204 Sep 2020Morning ShiftChemistrys Block ElementsActual

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

Options

  1. ALi 2 O 2 ,   Na 2 O and K 2 O 2
  2. BLi 2 O ,   Na 2 O 2 and KO 2
  3. CLi 2 O ,   Na 2 O and K 2 O 2
  4. DLi 2 O ,   Na 2 O 2 and K 2 O

Correct answer

B. Li 2 O ,   Na 2 O 2 and KO 2

Step-by-step solution

On heating in excess air Li form oxide sodium form peroxide while K , Rb , Cs form superoxide.

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