How many moles of electrons (how many Faradays of electricity) are required to reduce $1 \ mol$ of $MnO_4^-$ to $MnO_2$?

$A$ constant current $(0.5 \, A)$ is passed for $1 \, hour$ through $(i)$ aqueous $AgNO_3$,$(ii)$ aqueous $CuSO_4$ and $(iii)$ molten $AlF_3$,separately. The ratio of the mass of the metals deposited on the cathode is $[M_{Ag}, M_{Cu}, M_{Al}$ are molar masses of the respective metals.]

How much electricity in terms of Faraday is required for the reduction of $2 \ mol$ of $Cr_2O_7^{2-}$ into $Cr^{3+}$ in an acidic medium (in $F$)?

What is the volume of $H_2$ gas produced at $S.T.P.$ when $1 \ Faraday$ of electricity is passed through a dilute solution of acid (in $mL$)?

An electrolytic cell contains a solution of $Ag_{2}SO_{4}$ and has platinum electrodes. $A$ current is passed until $1.6 \ g$ of $O_{2}$ is liberated at the anode. The amount of silver deposited at the cathode would be ............ $g$.

Two different electrolytic cells filled with molten $Cu(NO_3)_2$ and molten $Al(NO_3)_3$ respectively are connected in series. When electricity is passed,$2.7 \ g$ of $Al$ is deposited on the electrode. Calculate the weight of $Cu$ deposited on the cathode. [Atomic mass: $Cu = 63.5$,$Al = 27.0 \ g \ mol^{-1}$] (in $g$)