During the discharging of a lead storage cell,the concentration of $H_2SO_4$ reduces from $40\% \ w/w$ to $30\% \ w/w$. Find the total charge produced in $faraday$. Given the volume of the solution $= 4.9 \ L$ and density $= 1.2 \ g/mL$. (Assume volume and density remain constant)

The electrochemical cell shown below is a concentration cell.
$M \mid M^{2+} (\text{saturated solution of a sparingly soluble salt, } MX_2) \mid M^{2+} (0.001 \ mol \ dm^{-3}) \mid M$
The emf of the cell depends on the difference in concentration of $M^{2+}$ ions at the two electrodes. The emf of the cell at $298 \ K$ is $0.059 \ V$.
$1.$ The solubility product $(K_{sp}; \ mol^3 \ dm^{-9})$ of $MX_2$ at $298 \ K$ based on the information available for the given concentration cell is (take $2.303 \times R \times 298 / F = 0.059 \ V$):
$(A) \ 1 \times 10^{-15} \quad (B) \ 4 \times 10^{-15}$
$(C) \ 1 \times 10^{-12} \quad (D) \ 4 \times 10^{-12}$
$2.$ The value of $\Delta G \ (kJ \ mol^{-1})$ for the given cell is (take $1 \ F = 96500 \ C \ mol^{-1}$):
$(A) \ -5.7 \quad (B) \ 5.7 \quad (C) \ 11.4 \quad (D) \ -11.4$
Give the answer for question $1$ and $2$.

Which of the following statements is $NOT$ correct?

If $\Lambda^{0}_{NaCl} = 126 \ S \ cm^{2} \ mol^{-1}$,$\Lambda^{0}_{KBr} = 125 \ S \ cm^{2} \ mol^{-1}$,and $\Lambda^{0}_{KCl} = 150 \ S \ cm^{2} \ mol^{-1}$,then find $\Lambda^{0}_{NaBr}$ in $S \ cm^{2} \ mol^{-1}$.

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.

During the electrolysis of carnallite,$MgCl_2$ is decomposed and not $KCl$. This is because of