Question

The solution of nickel sulphate, in which a nickel rod is dipped, has been diluted $10$ times. The potential of the nickel electrode:

• A. decreases by $60mV$
• B. increases by $30mV$
• C. decreases by $30mV$
• D. increases by $60mV$

Answer 1

The correct option is B increases by $30mV$

We know, $E=E^0-\frac{0.059}{2}log\left[{Ni}^{2t}\right]$

$E^1=E^0-\frac{0.059}{2}log\frac{\left[{Ni}^{2t}\right]}{10}$

$E-E^1=\frac{-0.059}{2}log\frac{\left[{Ni}^{2t}\right]}{\left[{Ni}^{2t}\right]/10}$

$E-E^1=-0.0295log10$

$=-0.0295\simeq -0.03$

$E^1=E+0.03V$

& $E^1=E+30mV$

$\therefore$ The potential of $Ni$ electrode increases by $30mV$.