Soln:

i. Concentration

• Is the amount of the electrolyte per liter of solution.
• The ion which is in higher concentration in a solution which is in higher concentration in a solution is favored for its discharge.
• For example; dilute hydrochloric acid which contains OH^- from H₂O and Cl^- from HCl because the concentration of OH^- is greater than that of Cl^-, OH^-, would be discharged in preference to the Cl^2-.

ii. Nature of the electrode

The nature of the electrodes, especially the cathode, sometimes influence the selection of the ion to be discharged for example in electrolytes of NaCl, Na⁺ and Cl^- ionize water, water itself release H⁺ and OH^-. If a platinum electrode (cathode) uses H⁺ is discharged as preference because is lower in electrochemical series. If a mercury cathode is used, Na⁺ is discharged as sodium metal is higher in the electrochemical series.