Question

Electrode potential of cadmium is $-0.4$V and electrode potential of chromium is $-0.74$V. $\left[C{d}^{2+}\right]=0.1$M and $\left[C{r}^{3+}\right]=0.01$M. Write the cell reaction.

Answer 1

Given that,

$C{r}^{3+}+3e^{-}⟶Cr;$ $E^o=-0.74V$

$C{d}^{2+}+2e^{-}⟶Cd;$ $E^o=-0.4V$

Thus the overall cell reaction for the $C{r}^{3+}|Cr$ and $C{d}^{2+}|Cd$ described above as follows:

$3C{d}^{2+}+2Cr\to 3Cd+2C{r}^{3+}$