Question

E.M.F. of $Ni\left(s\right)\left|{Ni}^{2+}\left(aq\right)\right|\left|{Cu}^{2+}\left(aq\right)\right|Cu\left(s\right)$ cell can be increased by__________.

• A. Increasing the concentration of $C{u}^{2+}$ ions
• B. Increasing the concentration of ${Ni}^{2+}$ ions
• C. Adding dimethyl glyoxime into the left half-cell
• D. Changing the electrolyte present in salt bridge

Answer 1

Answer: (A)

Increasing the concentration of $C{u}^{2+}$ ions

The cell reaction is-
$C{u}^{2+}(aq.)+Ni\left(s\right)\to N{i}^{2+}\left(aq\right)+Cu\left(s\right)$

$E_{Cell}=E_{Cell}^o-\frac{0.0591}{n}log\frac{\left[N{i}^{2+}\right]}{\left[C{u}^{2+}\right]}$

By increasing the conc. of $C{u}^{2+}$ ions E.M.F of the cell increases.