Cells $A$ and $B$ contain aqueous solutions of ferrous chloride $(FeCl_2)$ and ferric chloride $(FeCl_3)$ respectively. If the same quantity of electricity is passed through both cells, what is the ratio of the mass of iron deposited in cell $A$ to that in cell $B$?

Electrolytic cells containing $Zn$ and $Al$ salt solutions are connected in series. If $6.5 \ g$ of $Zn$ is deposited in one cell,calculate the mass of $Al$ deposited in the second cell (molar mass: $Zn=65 \ g \ mol^{-1}$,$Al=27 \ g \ mol^{-1}$) by passing a definite quantity of electricity. (in $g$)

Potassium chlorate is prepared by electrolysis of $KCl$ in basic solution as shown by the following equation:
$6 OH^{-} + Cl^{-} \rightarrow ClO_{3}^{-} + 3 H_{2}O + 6 e^{-}$
$A$ current of $x \ A$ has to be passed for $10 \ h$ to produce $10.0 \ g$ of potassium chlorate. The value of $x$ is $.......$ (Nearest integer).
(Molar mass of $KClO_{3} = 122.6 \ g \ mol^{-1}, F = 96500 \ C \ mol^{-1}$)

$A$ current of $0.5 \ A$ is passed through molten $AlCl_3$ for $96.5 \ s$. The mass of aluminium deposited at cathode is $x \ mg$ and volume of chlorine liberated (at $STP$) at anode is $y \ mL$. $x$ and $y$ are respectively

Consider the following reaction:
$MnO_4^- + 8H^{+} + 5e^- \rightarrow Mn^{2+} + 4H_2O$,$E^\circ = 1.51 \ V$
The quantity of electricity required in Faraday to reduce five moles of $MnO_4^-$ is ..... .

How much time (in $sec$) is required to coat a metal surface of $80 \, cm^2$ with a $0.005 \, mm$ thick layer of silver from a silver nitrate solution using a current of $3 \, A$? (Density of silver $= 10.5 \, g \, cm^{-3}$)