Question

The standard electrode potential for Ni²⁺/Ni couple is -0.25 V and for Ag⁺/Ag couple is 0.80 V. These two couples are connected to make an electrochemical cell. The redox reaction is spontaneous. The cell potential will be:

• A. + 1.05 V
• B. -1.05 V
• C. + 0.55 V
• D. -0.55 V

Hint:

Remember: E°cell = E°cathode - E°anode

Answer 1

The Correct Option is A

E°cell = E°cathode - E°anode = 0.80 V - (-0.25 V) = 1.05 V. Positive means spontaneous.