Question

Why is chlorine and water a disproportionation reaction?

Answer 1

I think you refer to the disproportionation of elemental chlorine to chloride anion, and hypochlorous acid....

Explanation:

And we can go thru the rigmarole of redox transtions…

`"Elemental chlorine is reduced (i):"`

`1/2Cl_2 +e^(-) rarr Cl^-`

`"Elemental chlorine is oxidized to hypochlorous acid (ii):"`

`1/2Cl_2 + H_2O(l) rarr HOstackrel(+I)Cl+ +H^+ +e^(-)`

And we adds `(i)+(ii)` to get....

`Cl_2 + H_2O(l) rarr HOstackrel(+I)Cl+ +HCl(aq)`

The given equation is balanced with respect to mass and charge, as indeed it MUST be if we purport to represent chemical reality...