Question

Oxidation state(s) of chlorine is \[CaOC{{l}_{2}}\] (bleaching powder) is /are?
a.) +1 and -1
b.) +1 only
c.) -1 only
d.) None of these

Answer 1

Hint: We know that chlorine can show different-different oxidation states. For finding the oxidation state of chlorine we have to balance the total charge on the given compound. And the oxidation state of calcium is fixed.

Complete step by step solution:
Oxidation number, also called oxidation state, the total number of electrons that an atom either gains or loses in order to form a chemical bond with another atom.
And the sum of the oxidation numbers of all of the atoms in a neutral compound is ‘0’. Chlorine can show different oxidation states like −1, +1, +2, +3, +4, +5, +6, +7.
Usually it shows -1, except in compounds with oxygen and fluorine. So, here the given compound \[CaOC{{l}_{2}}\]is with oxygen.
The molecule \[CaOC{{l}_{2}}\]can be written as\[Ca(OCl)Cl\]. It contains 2 Cl atoms of different oxidation states. The ion \[C{{l}^{-}}\]is in -1 oxidation state and in \[OC{{l}^{-}}\]ion is in +1 oxidation state. ‘Ca’ is always in +2 oxidation state. And to make this compound neutral we have to balance the charge.
Here the total sum of charge is equal to zero because it is a neutral compound.

So, the correct answer is “Option A”.

Note: Here you make sure that oxidation state should be balanced. And here the sum of the oxidation numbers in a polyatomic ion is equal to the charge of the ion. And in this compound there is no charge on it.