Question

When aqueous solution of KCl is electrolysed, resultant solution has:

• A. pH > 7
• B. pH < 7
• C. pH = 7
• D. initially less than 7 then increases

Answer 1

The correct option is A pH > 7

1. When the aqueous solution of KCl is electrolyzed, then it will dissociate into potassium and chlorine ions
2. KCl $\to$ K${}^{+}$ + Cl${}^{-}$
   
3. The chloride ion produced will attract the hydrogen ion from water molecule while potassium will not hydrolyze. The attraction of hydrogen ion by chloride ion will release OH${}^{-}$ ion.
4. Cl${}^{-}$ + H${}_2$O $\to$ HCl + OH${}^{-}$
5. The production of OH${}^{-}$ will make the solution basic (pH greater than 7)