For gold plating,the electrolyte used is

Electrolysis of aqueous copper $(II)$ sulphate between $Pt$ electrodes gives '$X$' at anode and '$Y$' at cathode. $X$ and $Y$ are respectively

Which species is obtained at the anode during the electrolysis of an aqueous solution containing a higher concentration of $H_2SO_4$?

Electrolysis of aqueous $HCl$ solution produces

Which of the following chemical reactions occurs at the anode during the electrolysis of a highly concentrated $H_2SO_4$ solution?

What is produced at the cathode during the electrolysis of aqueous $Na_2SO_4$?