For how much time,$10 \ A$ electric current should be passed through a dilute aqueous $NiSO_4$ solution during electrolysis using inert electrode,in order to get $5.85 \ g$ Nickel (in $s$)?
[At. mass of $Ni = 58.5 \ g/mol$]

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

How much electricity in terms of Faraday is required to produce $40.0 \text{ g}$ of $\text{Al}$ from molten $\text{Al}_2\text{O}_3$ (in $\text{ F}$)?

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 $= 52$)

What is the quantity of electricity (in Coulombs) required to deposit all the silver from $250 \text{ mL}$ of $1 \text{ M AgNO}_3$ solution?

The number of Faradays $F$ required to produce $20 \ g$ of calcium from molten $CaCl_2$ (Atomic mass of $Ca = 40 \ g \ mol^{-1}$) is