Consider the following relations for emf of an electrochemical cell:
(i) EMF of cell = (Oxidation potential of anode) – (Reduction potential of cathode)(ii) EMF of cell = (Oxidation potential of anode) + (Reduction potential of cathode)(iii)) EMF of cell = (Reductional potential of anode) + (Reduction potential of cathode)(iv) ) EMF of cell = (Oxidation potential of anode) – (Oxidation potential of cathode)