Question

How come analysis of commercial bleaching solutions will often show a lower `OCl^-` ion content than is advertised on the bottle?

Answer 1

Well, I presume redox processes can occur in the bottle....

Explanation:

i.e. `"by means of oxidation of oxide and reduction of chloriee..."`...`ClO^(-) + rarr Cl^(-) + 1/2O_2`

...`"or by means of disproportionation"`...

`3""^(-)OCl + rarr 2Cl^(-) + ClO_3^-`