Question

$E$ value for the cell reaction is :

$Cu|{Cu}^{2+}\left(0.001M\right)||{Cu}^{2+}\left(0.1M\right)|Cu$

• A. $-\frac{RT}{2F}\ln \left(0.01\right)$
• B. $-\frac{RT}{2F}\ln \left(0.1\right)$
• C. $+\frac{RT}{F}\ln \left(0.01\right)$
• D. $\frac{RT}{F}\ln \left(0.1\right)$

Answer 1

Answer: (A)

$-\frac{RT}{2F}\ln \left(0.01\right)$

$Cu|{Cu}^{2+}\left(0.001M\right)||{Cu}^{2+}\left(0.1M\right)|Cu$

$Cu\to {Cu}^{2+}+2e^{-}$

${Cu}^{2+}+2e^{-}\to Cu$ $\left(n=2\right)$

____________________________________

$Cu+{Cu}^{2+}\left(0.1M\right)\to {Cu}^{+2}+Cu\left(0.001M\right)$

$E_{cell}^o=0$

$E=E_{cell}^o-\frac{RT}{nF}\ln \frac{\left[P\right]}{[R]}$

$=0-\frac{RT}{2\times F}\ln \frac{0.001}{0.1}$

$=-\frac{RT}{2F}\ln \frac{{10}^{-3}}{{10}^{-1}}$

$=-\frac{RT}{2F}\ln {10}^{-3+1}$

$=-\frac{RT}{2F}\ln {10}^{-2}$

$=-\frac{RT}{2F}\ln \left(0.01\right)$

$E$ value for the cell reaction is $\frac{-RT}{2F}\ln 0.01$