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JEE Main 201815 AprilEvening ShiftOnline

Exam: JEE Main
Year: 2018
Date: 15 April
Shift: Evening Shift
Mode: Online
Subject: Chemistry
Chapter: s Block Elements

JEE Main 2018 · 15 April · Evening Shift · Online · Chemistry · s Block Elements

In KO_2 , the nature of oxygen species and the oxidation state of...

In

\mathrm{KO}_2

, the nature of oxygen species and the oxidation state of oxygen atom are, respectively:

Options

ASuperoxide and $-1$
BSuperoxide and $-1 / 2$
CPeroxide and $-1 / 2$
DOxide and $-2$

Correct answer

B. Superoxide and $-1 / 2$

Step-by-step solution

In

\mathrm{KO}_2

, the nature of oxygen species and the oxidation state of oxygen atom are superoxide (superoxide ion is

\mathrm{O}_2^{-}

)

and -1 / 2

respectively. Let

x

be oxidation state of oxygen. The oxidation state of

\mathrm{K}

is

+1

. Hence

\begin{gathered} +1+2(x)=0 \\ 2 x=-1 \\ x=-\frac{1}{2} \end{gathered}

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