Calculate the time required in seconds to deposit $6.35 \ g$ of copper from its salt solution by passing a $5 \ A$ current. [Molar mass of $Cu = 63.5 \ g \ mol^{-1}$]

$A$ current of $0.01 \ A$ is passed through a solution of a metal bromide $(MBr_x)$. The only reaction at the cathode is the deposition of metal $(M)$. After $3 \ hours$,$0.072 \ g$ of metal $(M)$ is deposited. The value of '$x$' is approximately (Given: Atomic weight of $M = 192$)

The unit of electrochemical equivalent is

The quantity of electricity required to liberate $112 \, cm^3$ of hydrogen at $STP$ from acidified water is

The mass of carbon anode consumed (giving only carbon dioxide) in the production of $270 \ kg$ of aluminium metal from bauxite by the Hall process is ............... $kg$.

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 $Ag = 107.9$; $Au = 197$].