Question

The correct representation of Nernst’s equation for half-cell reaction
$C{u}^{2+}\left(aq\right)+e^{-}\to C{u}^{+}\left(aq\right)$ is

• A. $E_{C{u}^{+},C{u}^{2+}}^{\circ }=E_{C{u}^{+},C{u}^{2+}}^{\circ }-\frac{0.0592}{2}log\frac{\left[C{u}^{+}\right]}{\left[C{u}^{2+}\right]}$
• B. $E_{C{u}^{+},C{u}^{2+}}=E_{C{u}^{+},C{u}^{2+}}^{\circ }-\frac{0.0592}{1}log\frac{\left[C{u}^{+}\right]}{\left[C{u}^{2+}\right]}$
• C. $E_{C{u}^{+},C{u}^{2+}}^{\circ }=E_{C{u}^{+},C{u}^{2+}}-\frac{0.0592}{2}log\frac{\left[C{u}^{+}\right]}{\left[C{u}^{2+}\right]}$
• D. $E_{C{u}^{+},C{u}^{2+}}=E_{C{u}^{+},C{u}^{2+}}^{\circ }-\frac{0.0592}{1}log\frac{\left[C{u}^{+}\right]}{\left[C{u}^{2+}\right]}$

Answer 1

Answer: (B), (D)

Key Idea General Nernst equation for a reaction is given as

$E_{\text{call }}=E_{\text{cell }}^{\circ }-\frac{0.0591}{x}\log \frac{[P]}{[R]}$

For the half-cell

$C{u}^{2+}(aq)+e^{-}\to C{u}^{+}(aq)$

The correct Nernst's equation is

$E_{C{u}^{+}},C{u}^{2+}=E_{C{u}^{+}}^{\circ },C{u}^{2+}-\frac{0.0591}{1}log\frac{\left[C{u}^{+}\right]}{\left[C{u}^{2+}\right]}$