Question

In all oxides, peroxides and superoxides, the oxidation state of alkali metals is :

• A. +1 and -1
• B. +1 and +2
• C. +1 only
• D. +1, -1 and +2

Answer 1

Answer: (C)

+1 only

Generally all these oxides the oxidation state of the alkali metal is +1. The calculation of metal oxidation state is shown below:

$M_{2}O:2x+(-2)=0\Rightarrow x=+1$

(in oxide O is present as $O^{2-}$ )

$M_2{O}_2:2x+(-2)=0\Rightarrow x=+1$

(in peroxide O is present as $O_2^{2-}$ )

$M{O}_2:x-1=0\Rightarrow x=+1$

(in superoxide O is present as $O_2^{-}$