In the electrolysis of an aqueous $NiI_2$ solution using $Ni$ electrodes,what happens to the mass of the cathode upon passing $1$ equivalent of charge? (Given: atomic mass of $Ni = 59$)

On passing $C$ ampere of electricity through an electrolyte solution for $t$ seconds,$m$ grams of metal are deposited on the cathode. The equivalent weight $E$ of the metal is:

For the oxidation of $0.2 \text{ M} \text{ FeSO}_4$ solution,$0.965 \text{ A}$ current is passed through it for $1 \text{ hour}$. The volume of the solution that is oxidised in $\text{mL}$ is:

To gain $1 \ mole$ $Mg$ from $Mg^{2+}$ and $1 \ mole$ $Al$ from $Al^{3+}$,how many Coulombs of electricity are required respectively?

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 $= 52$)

An electric current is passed through a silver voltameter connected to a water voltameter. The cathode of the silver voltameter weighed $0.108 \ g$ more at the end of the electrolysis. The volume of oxygen evolved at $STP$ is ............... $cm^{3}$.