Question

What is potential of platinum wire dipped into a solution of $ 0.1\,M\,in\,S{{n}^{2+}} $ and $ 0.01\,M\,in\,S{{n}^{4+}} $ ?

• A. $ E{}^\circ $
• B. $ E{}^\circ +0.059 $
• C. $ E{}^\circ +\frac{0.059}{2} $
• D. $ E{}^\circ -0.059 $
• E. $ E{}^\circ -2\times 0.59 $

Answer 1

Answer: (C)

$ S{{n}^{2+}}\xrightarrow{{}}S{{n}^{4+}}+2{{e}^{-}} $ $ {{E}_{cell}}=E{}^\circ -\frac{0.059}{n}\log \frac{[S{{n}^{4+}}]}{[S{{n}^{2+}}]} $ $ =E{}^\circ -\frac{0.059}{2}\log \left[ \frac{0.01}{0.1} \right] $ $ =E{}^\circ -\frac{0.059}{2} $