To deposit one $gm$ equivalent of an element at an electrode,the quantity of electricity needed is

The electrolytic cells,one containing acidified ferrous chloride and another acidified ferric chloride,are connected in series. The ratio of iron deposited at the cathodes in the two cells when electricity is passed through the cells will be:

The atomic weights of silver and copper are $108$ and $64$ respectively. $A$ silver voltameter and a copper voltameter are connected in series,and when current is passed,$10.8 \ g$ of silver is deposited. The mass of copper deposited will be ............. $g$.

When $1 \ F$ of electricity is passed through acidulated water,the volume of $O_2$ evolved at $STP$ is ............. $dm^{3}$.

$5 \ A$ 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 $\%$)

Which of the following aqueous solutions will result in the maximum number of moles of metal deposited on passing the same amount of charge?