$250 \ mL$ of a waste solution obtained from the workshop of a goldsmith contains $0.1 \ M \ AgNO_3$ and $0.1 \ M \ AuCl$. The solution was electrolyzed at $2 \ V$ by passing a current of $1 \ A$ for $15 \ minutes$. The metal/metals deposited will be
$(E^0_{Ag^+/Ag} = 0.80 \ V, E^0_{Au^+/Au} = 1.69 \ V)$

Electricity is passed through an acidic solution of $Cu^{2+}$ until all the $Cu^{2+}$ is exhausted, leading to the deposition of $300 \ mg$ of $Cu$ metal. Subsequently, a current of $600 \ mA$ is passed through the same solution for another $28 \ minutes$ while keeping the total volume of the solution fixed at $200 \ mL$. The total volume of oxygen evolved at $STP$ during the entire process is . . . . . . $mL$. (Nearest integer) [Given: $Cu^{2+}_{(aq)} + 2e^{-} \rightarrow Cu_{(s)}$, $E_{red}^0 = +0.34 \ V$; $O_{2(g)} + 4H^{+} + 4e^{-} \rightarrow 2H_2O$, $E_{red}^0 = +1.23 \ V$; Molar mass of $Cu = 63.54 \ g \ mol^{-1}$; Faraday Constant $= 96500 \ C \ mol^{-1}$; Molar volume at $STP = 22.4 \ L$]

How many Coulombs of electricity are required for the oxidation of one mol of water to dioxygen?

How many electrons would be required to deposit $6.35 \ g$ of copper at the cathode during the electrolysis of an aqueous solution of copper sulphate? (Atomic mass of copper $= 63.5 \ u$,$N_A =$ Avogadro's constant)

The electrochemical equivalent of a metal is $3.3 \times 10^{-7} \ kg/C$. The mass of the metal liberated at the cathode when a $3 \ A$ current is passed for $2 \ s$ will be:

Total charge on $1 \, \text{mole}$ of a monovalent metal ion is equal to