What are the products obtained at the cathode and anode during the electrolysis of the following when platinum electrodes are used in the electrolysis

a) During the electrolysis of molten KCl using platinum electrodes. Potassium is obtained at cathode and chlorine at anode.
`2CKl to 2K^(+)+2C^(-)`
`2Cl^(-) to Cl_(2)+2e^(-)` (anode)
`2K^(+)+2e^(-) to 2K` (cathode)
b) During the electrolysis of aq.` CuSO_(4)` solution using platinum electrodes, `O_(2)` gas liberated at anode and Cu deposited at cathode.
`2 CuSO_(4)to 2 Cu^(+2)+2SO_(4)^(-2)`
`2Cu^(+2)+4e^(-) 2 Cu` (cathode)
`2H_(2)O -4e^(-)to O_(2)+4H^(+)` (anode)
During the electrolysis of `aq. K_(2)SO_(4)` using pt-anode and pt-cathode hydrogen gas liberated at cathode and oxygen gas at anode.
`K_(2)SO_(4) to 2K^(+)+SO_(4) ^(-2)`
`4 H_(2) O overset(+4e ^(-))to2H_(2) +4OH^(-)`(cathode)
`2H_(2)Ooverset(-4e^(-))toO_(2)+ 4H^(+)` (anode)