$A$ certain current liberated $0.504 \ g$ of hydrogen in $2 \ hours$. How many grams of copper can be liberated by the same current flowing for the same time in a copper sulphate solution?

$Al_2O_3$ is reduced by electrolysis at low potential and high current. If a current of $4 \times 10^4 \ A$ is passed through molten $Al_2O_3$ for $6 \ h$,how many grams of $Al$ will be produced? (Assume $100\%$ current efficiency and atomic mass of $Al = 27 \ g \ mol^{-1}$)

Match the column :-

Column $I$ (Reduction process)	Column $II$ (Charge required)
$(a)$ $1$ mol of $MnO_4^-$ to $Mn^{2+}$	$(p)$ $193000$ $C$
$(b)$ $1$ mol of $Cr_2O_7^{2-}$ to $Cr^{3+}$	$(q)$ $289500$ $C$
$(c)$ $1$ mol of $Sn^{4+}$ to $Sn^{2+}$	$(r)$ $482500$ $C$
$(d)$ $1$ mol of $Al^{3+}$ to $Al$	$(s)$ $579000$ $C$

$A$ metal surface of $100 \, cm^2$ area has to be coated with a nickel layer of thickness $0.001 \, mm$. $A$ current of $2 \, A$ was passed through a solution of $Ni(NO_3)_2$ for '$x$' seconds to coat the desired layer. The value of $x$ is $.........$. (Nearest integer)
($\rho_{Ni}$ (density of Nickel) is $10 \, g \cdot cm^{-3}$,Molar mass of Nickel is $60 \, g \cdot mol^{-1}$,$F = 96500 \, C \cdot mol^{-1}$)

How much charge in coulombs is required for the reduction of one mole of $Al^{3+}$ to $Al$?

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 $= 10.5 \, g \, cm^{-3}$)