Question

Standard reduction potentials of $ S{{n}^{2+}}/Sn $ and $ Z{{n}^{2+}}/Zn $ electrodes are 0.14 V and $ -\text{ }0.74\text{ V} $ respectively. What is the $ {{\text{E}}^{\text{o}}} $ of the following cell in volts $ \text{Zn/Z}{{\text{n}}^{2+}}||S{{n}^{2+}}/Sn $ ?

• A. $ -0.6 $
• B. $ -0.88 $
• C. 0.88
• D. 0.6

Answer 1

Answer: (D)

$ {{E}^{o}}_{cell}={{E}_{cathode}}-{{E}_{anode}} $ $ {{E}_{cathode(S{{n}^{2+}}/Sn)}}=-0.14 $ $ {{E}_{anode(Z{{n}^{2+}}/Zn)}}=-0.74 $ $ {{E}^{o}}_{cell}=-0.14-(-0.74) $ $ =0.74-0.14 $ $ =0.6\,\text{V} $