Question

What is the electrolysis of concentrated potassium chloride in aqueous solutions?

Answer 1

It means the charge is taken away from the potassium and chloride ions at the electrodes.

Explanation:

The solution may be represented by `K^+(aq) and Cl^(-)(aq)`

At the positive electrode (anode) the following happens:
`Cl^- ->Cl+e^-`
`2Cl->Cl_2(g)`

At the other side (cathode):
`K^+ +e^(-) ->K`
`K+H_2O->K^+ +OH^- +H`
`2H->H_2(g)`

So the net result is that at the anode chlorine gas is released, at the cathode hydrogen gas is released, and a strong solution of potassium hydroxide is left in the container:

`2KCl(aq)+2H_2O->2KOH(aq)+H_2(g)+Cl_2(g)`