Chemistry - Complete d-block Question with Solution | TestHub

${\mathrm{Mn}}^{2+}$ does not displace ${\mathrm{H}}_2$ from dilute acid because they are less reactive $\left(\mathrm{SRP}\hspace{0.17em}\mathrm{value}\right)$. 

Given below are SRP values,
${\mathrm{H}}_2\mathrm{O}|{\mathrm{H}}_2=-0.8277, {\mathrm{Mn}}^{2+}|\mathrm{Mn}=-1.185 \mathrm{V}$