${\mathrm{E}}_{{\mathrm{M}}^{+2}/\mathrm{M}}^0$value is more negative than expected for all the following except

Due to stable configuration of ${\mathrm{Mn}}^{+2} \mathrm{and} {\mathrm{Zn}}^{+2}$ theier ${\mathrm{E}}_{{\mathrm{M}}^{+2}/\mathrm{M}}^0$ values are more negative than expected. 

Due to high hydration enthalpy of  ${\mathrm{Ni}}^{+2}$ its ${\mathrm{E}}_{{\mathrm{M}}^{+2}/\mathrm{M}}^0$ value is more negative. 

${\mathrm{E}}_{{\mathrm{M}}^{+2}/\mathrm{M}}^0$ of cpper is positive due to high hydration enthalpy of  ${\mathrm{Cu}}^{+2}$