When a current of $2 \ A$ is passed for $2 \ hours$ through a copper voltameter,$W \ g$ of copper is deposited. If a current of $1 \ A$ is passed for $4 \ hours$ through the same voltameter,how much copper will be deposited?

On passing a current of $1.2 \ A$ through a solution of salt of copper for $40 \ min$,$0.96 \ g$ of copper was deposited. The equivalent weight of copper in $g$ is

$A$ certain quantity of electricity is passed through an aqueous solution of $AgNO_3$ and a cupric salt solution connected in series. The amount of $Ag$ deposited is $1.08 \ g$. The amount of copper deposited is ............. $g$ (atomic weight of $Cu = 63.5$; $Ag = 108$).

An acidic solution of dichromate is electrolyzed for $8 \ min$ using $2 \ A$ current. As per the following equation: $Cr_{2}O_{7}^{2-} + 14H^{+} + 6e^{-} \rightarrow 2Cr^{3+} + 7H_{2}O$. The amount of $Cr^{3+}$ obtained was $0.104 \ g$. The efficiency of the process (in $\%$) is (Take: $F = 96000 \ C$,At. mass of chromium $= 52$)

Equal amounts of electricity are passed through two separate electrolytic cells containing nickel nitrate $[Ni(NO_3)_2]$ and chromium nitrate $[Cr(NO_3)_3]$. If $0.3 \ g$ of nickel is deposited in the first cell,how much chromium will be deposited in the second cell? (Atomic mass of $Ni = 59$,Atomic mass of $Cr = 52$)

Potassium chlorate is prepared by the electrolysis of $KCl$ in basic solution:
$6 OH^{-} + Cl^{-} \rightarrow ClO_{3}^{-} + 3 H_{2}O + 6 e^{-}$
If only $60\%$ of the current is utilized in the reaction,the time (rounded to the nearest hour) required to produce $10 \ g$ of $KClO_{3}$ using a current of $2 \ A$ is:
(Given: $F = 96,500 \ C \ mol^{-1}$,molar mass of $KClO_{3} = 122 \ g \ mol^{-1}$)