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 $F$)?

$250 \ mL$ of a waste solution obtained from the workshop of a goldsmith contains $0.1 \ M \ AgNO_3$ and $0.1 \ M \ AuCl$. The solution was electrolyzed at $2 \ V$ by passing a current of $1 \ A$ for $15 \ minutes$. The metal/metals deposited will be
$(E^0_{Ag^+/Ag} = 0.80 \ V, E^0_{Au^+/Au} = 1.69 \ V)$

What amount of electricity can deposit $1 \ mole$ of $Al$ metal at cathode when passed through molten $AlCl_3$?

Three voltameters containing aqueous solutions of $H_{2}SO_{4}$,$CuSO_{4}$,and $AgNO_{3}$ are connected in series as shown in the figure. $A$ current was passed for $10 \ hours$. $10.8 \ g$ of $Ag$ was deposited at the cathode in the $(III)$ electrolytic cell during electrolysis,given that the current efficiency is $50 \%$. If $Z_{1}$,$Z_{2}$,and $Z_{3}$ are the electrochemical equivalents for the formation of $H_{2}$,$Cu$,and $Ag$ respectively,then the ratio $Z_{1} : Z_{2} : Z_{3}$ is:

Solutions of $Hg_{2}(ClO_{4})_{2}$,$Hg(ClO_{4})_{2}$,$CuSO_{4}$,and $AgNO_{3}$ are connected in series. If a current of $2.58 \ A$ is passed for $1 \ hour$,calculate the moles of metal liberated from each solution at the cathode.

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