On electrolysis in which of the following, `O_(2)` would be liberated at the anode?

Which of the following on electrolysis would, not evolve oxygen at the anode ?

In presence of Pt-electrodes, electrolysis of the following aqueous solutions are carried out. In which of the following cases, the substances liberated at the cathode and anode will be the same -

The compound which on electrolysis in its molten or liquid state liberates hydrogen at anode is -

During electrolysis of molten ICl3, both I_2 and Cl_2 are liberated at anode /cathode.

Electrolysis of aqueous copper sulphate solution liberates which of the following gases at the anodes ?