Faraday's laws of electrolysis will fail when

On passing $C$ ampere of current for time $t$ seconds through $1 \ L$ of $2 \ M$ $CuSO_4$ solution (atomic weight of $Cu = 63.5$),the amount $m$ of $Cu$ (in grams) deposited on the cathode will be:

The quantity of electricity required to liberate $5600 \ mL$ of $H_2$ at $STP$ is the same as that required to liberate how many grams of silver (equivalent weight = $108$)?

The negative $Zn$ pole of a Daniel cell,sending a constant current through a circuit,decreases in mass by $0.13 \ g$ in $30$ minutes. If the electrochemical equivalent of $Zn$ and $Cu$ are $32.5$ and $31.5$ respectively,the increase in the mass of the positive $Cu$ pole in this time is .............. $g$.

Mass in grams of copper deposited by passing $9.6487 \ A$ current through a voltmeter containing copper sulphate solution for $100 \ s$ is (Given : Molar mass of $Cu: 63 \ g \ mol^{-1}, 1 \ F=96487 \ C$ ) (in $g$)

The number of $Faradays$ needed to reduce $4 \ g$ equivalents of $Cu^{++}$ to $Cu$ metal will be: