30. (i) Write equations to show how X and Y form ions.   31. (ii) If Y is a diatomic gas, write the equation for the direct combination of X and Y to form a compound.   32. (iii) Write two applications of electrolysis in which the anode diminishes in mass.   33. (iv) If the compound formed between X and Y is melted and an electric current passed through the molten compound, the element X will be obtained at the ........... and Y at the ........... of the electrolytic cell. (Provide the missing words.)