When 0.1 mole $Mn{O}_4^{2-}$ is oxidised, the quantity of electricity required to completely oxidise $Mn{O}_4^{2-}$ to $Mn{O}_4^{-}$ is

$\therefore$$Mn{O}_4^{2-}\underset{[=1F]}{\overset{1mole{e}^{-}}{\to }}Mn{O}_4^{-}$

  (+6)                                (+7)
As per the equation, for 1 mole of $Mn{O}_4^{2-}$, 1F of electricity is required. Thus, for 0.1 mole of $Mn{O}_4^{2-}$, 0.1F of electricity is required.
Since, 1F = 96500 C
$\therefore$ 0.1F = 0.1 x 96500 C = 9650 C
Hence; 9650 C is electricity is required to completely oxidase $Mn{O}_4^{2-}$ to $Mn{O}_4^{-}$.