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Q.
The compound formed upon combustion of potassium metal in excess air is
J & K CETJ & K CET 2015The s-Block Elements
Solution:
The compound formed upon combustion of potassium metal in excess air is potassium superqxide.
$K \stackrel{ O _{2}}{\longrightarrow } \underset{\text { Oxide }}{ K _{2} O } \stackrel{ O _{2}}{\longrightarrow } \underset{\text { Peroxide }}{ K _{2} O _{2}} \stackrel{ O _{2}}{\longrightarrow } \underset{\text { Superoxide }}{ KO _{2}}$