If a steady current of $4 \, A$ is maintained for $40 \, min$,depositing $4.5 \, g$ of zinc at the cathode,then the electrochemical equivalent $(Z)$ will be:

$5 \ A$ current is passed through $AgNO_3$ solution for $193 \ s$. If $0.972 \ g$ of $Ag$ is deposited,calculate the current efficiency (cell capacity) of the electrolytic cell. $[Ag = 108 \ u]$ (in $\%$)

How many seconds of current at $9.65 \ A$ must be passed through a solution of $Al^{3+}$ to obtain $1 \ \text{millimole}$ of $Al$ metal?

The density and equivalent weight of a metal are $10.5\, g\, cm^{-3}$ and $100$,respectively. The time required for a current of $3\, A$ to deposit a $0.005\, mm$ thick layer of the same metal on an area of $80\, cm^2$ is closest to $....\, s$

$A$ 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 same quantity of electricity was passed through solutions of salts of elements $X$,$Y$,and $Z$ with atomic masses $7$,$27$,and $48$ respectively. The masses of $X$,$Y$,and $Z$ deposited were $2.1 \ g$,$2.7 \ g$,and $7.2 \ g$ respectively. The valencies of $X$,$Y$,and $Z$ respectively are: