If a current of $0.4 \ A$ is passed through acidic water for $30 \ minutes$,calculate the volume of hydrogen gas produced at $STP$ in liters.

What is the number of moles of electrons passed when a current of $2 \text{ A}$ flows through a solution of an electrolyte for $10 \text{ minutes}$?

$A$ current of $0.25 \, A$ is passed through $CuSO_4$ solution placed in a voltameter for $45 \, minutes$. The amount of $Cu$ deposited on the cathode is ............. $g$ $(At. \, weight \, of \, Cu = 63.6)$.

The weight of silver $(at. \ wt. = 108)$ displaced by a quantity of electricity which displaces $5600 \ mL$ of $O_2$ at $STP$ will be ............ $g.$

In two separate experiments,the same quantity of electricity was passed through silver and gold solutions. The amounts of $Ag$ and $Au$ deposited are $2.15 \ g$ and $1.31 \ g$,respectively. The valency of gold is [Atomic mass of $Ag = 107.9$; $Au = 197$].

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 ............ $g$.