An Intriguing Electrochemical Cell Experiment
What is the overall electric cell potential of the electrochemical cell?
Which value represents the overall electric cell potential?
A. –0.13 V
B. –0.93 V
C. +0.67 V
D. +0.93 V
Answer:
+ 0.93V
The overall electric cell potential of the electrochemical cell is +0.93V. This value is obtained by calculating the difference between the standard reduction potentials (Eo) of the cathode and anode half-reactions.
For the given half-reactions:
- Ag⁺(aq) + e⁻ → Ag(s) Eo = +0.80 V
- Pb²⁺(aq) + 2e⁻ → Pb(s) Eo = –0.13 V
By combining the half-reactions, we get:
- 2Ag⁺(aq) + 2e⁻ → 2Ag(s) Eo = +0.80 V
- Pb(s) → Pb²⁺(aq) + 2e⁻ Eo = +0.13 V
- 2Ag⁺(aq) + Pb(s) → 2Ag(s) + Pb²⁺(aq)
Using the formula Ecell = Eo cathode - Eo anode, we find:
Ecell = 0.80V - (- 0.13V) = 0.80V + 0.13V = +0.93V
Therefore, the overall electric cell potential of the electrochemical cell is +0.93V.