Question

The oxidation state of $Cl$ in $CaOC{l}_2$ is

• A. -1
• B. +1
• C. +2
• D. -2

Answer 1

Answer: (A), (B)

The correct options are
A

-1

B

+1

$CaOC{l}_2$ : In the moelcular formula, bleaching powder has two $Cl$ atoms. Now, let us look at $CaOC{l}_2$ as $Ca\left(OCl\right)Cl$.

We can think of it as having a Chloride $C{l}^{-}$ ion and a hypochlorite ion $OC{l}^{-}$. Clearly, for $C{l}^{-}$, the oxidation state is -1.

Among $O$ and $Cl$, $O$ is more electronegative and thus it will have the negative oxidation state. The overall oxidation state of $OC{l}^{-}$ is -1. Apart from the elemental state and peroxide linkages, $O$ has an oxidation state of -2.

Let the oxidation state of $Cl$ in $OC{l}^{-}$ be n.

$⟹(-2)+n=-1$ or n = +1