The amount of charge required to liberate $9 \ g$ of aluminium (atomic weight = $27$ and valency = $3$) in the process of electrolysis is ......... $coulombs$ (Faraday's constant $= 96500 \ C \ mol^{-1}$)

How long a current of $3 \, A$ has to be passed through a solution of $AgNO_3$ to coat a metal surface of $80 \, cm^2$ with $0.005 \, mm$ thick layer? Density of $Ag$ is $10.5 \, g/cm^3$. (Answer in $sec$)

$38.6 \ A$ of current is passed for $100 \ s$ through an aqueous $CuSO_4$ solution using platinum electrodes. The mass of copper deposited from the solution and the volume of gas liberated at $STP$ are respectively (molar mass of $Cu = 63.54 \ g \ mol^{-1}$)

$A$ silver voltameter is connected in series with a water voltameter and an electric current is passed through them. At the end of electrolysis,the weight of the cathode in the silver voltameter increases by $0.108 \ g$. What is the volume of oxygen liberated at $STP$ in $mL$?

The mass of zinc produced by the electrolysis of zinc sulphate solution with a steady current of $0.015 \ A$ for $15$ minutes is . . . . . . $ \times 10^{-4} \ g$. (Atomic mass of zinc $= 65.4 \ amu$)

What mass of silver (Atomic mass = $108 \text{ g/mol}$) is deposited by a quantity of electricity that displaces $5600 \text{ mL}$ of $O_2$ gas at $STP$ (in $\text{ g}$)?