During electrolysis of aqueous $NaOH$,$4 \ g$ of $O_2$ gas is liberated at $NTP$ at the anode. The volume of $H_2$ gas liberated at the cathode in $litres$ is $..............$

Given that $Ni^{2+}/Ni = -0.25 \ V$; $Cu^{2+}/Cu = 0.34 \ V$; $Ag^{+}/Ag = 0.80 \ V$; $Zn^{2+}/Zn = -0.76 \ V$. Which of the following reactions under standard conditions will not take place in the specified direction?

Copper from copper sulphate solution can be displaced by .............. The standard reduction potentials of some electrodes are given below:
$E^o (Fe^{2+}, Fe) = -0.44 \ V$
$E^o (Zn^{2+}, Zn) = -0.76 \ V$
$E^o (Cu^{2+}, Cu) = +0.34 \ V$
$E^o (Cr^{2+}, Cr) = -0.74 \ V$
$E^o (H^{+}, 1/2H_2) = 0.00 \ V$

Molar conductances of $BaCl_2$,$H_2SO_4$,and $HCl$ at infinite dilutions are $x_1, x_2$,and $x_3$,respectively. Equivalent conductance of $BaSO_4$ at infinite dilution will be

Calculate the standard cell potentials of galvanic cells in which the following reactions take place:
$(i)$ $2Cr_{(s)} + 3Cd^{2+}_{(aq)} \rightarrow 2Cr^{3+}_{(aq)} + 3Cd_{(s)}$
$(ii)$ $Fe^{2+}_{(aq)} + Ag^{+}_{(aq)} \rightarrow Fe^{3+}_{(aq)} + Ag_{(s)}$
Calculate the $\Delta_r G^\Theta$ and equilibrium constant of the reactions.

All the energy released from the reaction $X \rightarrow Y, \Delta_{r}G^0 = -193 \ kJ \ mol^{-1}$ is used for oxidizing $M^{+}$ as $M^{+} \rightarrow M^{3+} + 2e^-, E^0 = -0.25 \ V$. Under standard conditions,the number of moles of $M^{+}$ oxidized when one mole of $X$ is converted to $Y$ is $\left[F = 96500 \ C \ mol^{-1}\right]$.