Question

What is the electrode potential (in volt) of the following electrode at $25^{\circ}C$ ?
$ Ni^{2+} (0.1\, M) | Ni_{(g)}$
standard reduction potential of $Ni^{2+} / Ni$ is $- 0.25 \,V$, $\left(\frac{2.303RT}{F} =0.06\right)$

• A. $-0.82 \,V$
• B. $-0.22 \,V$
• C. $-0.28 \,V$
• D. $-0.34 \,V$

Answer 1

Answer: (C)

By Nernst equation
$E=E^{\circ}-\frac{RT}{nF}$
ln $\left[\frac{Ni_{\left(s\right)}}{Ni^{2+}}\right]=-0.25-\frac{0.06}{2}log\left[\frac{1}{0.1}\right]$
$=-0.25-0.03$
$=-0.28\,V$