How much electricity in terms of Faraday is required to reduce $2 \ mol$ of $MnO_4^{-}$ into $Mn^{2+}$?

The quantity of electricity required for the complete electrolysis of $2 \ mol$ of $Na^{+}$ is = ....... Coulombs.

When $10 \,A$ current is passed for $80 \,min$, the volume of hydrogen gas liberated at $STP$ is: (in $\,L$)

The quantity of electricity needed to liberate $0.5 \ g$ equivalent of an element is

$A$ certain quantity of electricity is passed through an aqueous solution of $AgNO_3$ and a cupric salt solution connected in series. The amount of $Ag$ deposited is $1.08 \ g$. The amount of copper deposited is ............. $g$ (atomic weight of $Cu = 63.5$; $Ag = 108$).

$2.5 \, F$ of electricity are passed through a $CuSO_4$ solution. The number of gram equivalents of $Cu$ deposited on the cathode is $....$