$A$ hydrogen electrode is immersed in a solution with $pH = 0$ $(HCl)$. By how much will the potential (reduction) change if an equivalent amount of $NaOH$ is added to the solution? (Take $pH_2 = 1 \ atm$,$T = 298 \ K$).

Consider the following redox reaction :
$MnO_4^{-} + H^{+} + H_2C_2O_4 \rightleftharpoons Mn^{2+} + H_2O + CO_2$
The standard reduction potentials are given as below $(E_{red}^{\circ})$ :
$E_{MnO_4^{-} / Mn^{2+}}^{\circ} = +1.51 \ V$
$E_{CO_2 / H_2C_2O_4}^{\circ} = -0.49 \ V$
If the equilibrium constant of the above reaction is given as $K_{eq} = 10^x$,then the value of $x = $ . . . . . . (nearest integer).

For the fuel cell reaction:
$2H_{2(g)} + O_{2(g)} \to 2H_2O_{(l)}$; $\Delta_fH^o_{298}(H_2O_{(l)}) = -285.5 \ kJ/mol$
What is $\Delta S^o_{298}$ for the given fuel cell reaction?
Given: $O_{2(g)} + 4H^+_{(aq)} + 4e^- \to 2H_2O_{(l)}$; $E^o = 1.23 \ V$

Calculate the $K_C$ and $\Delta G^o$ for the chemical reaction :
$Ni_{(s)} + 2Ag_{(aq)}^{+} \to Ni_{(aq)}^{2+} + 2Ag_{(s)}$ $ [E^o = 1.05 \, V] $

$100 \text{ mL}$ of $0.2 \text{ M}$ acetic acid is completely neutralized using a standard solution of $NaOH$. The volume of ethane obtained at $STP$ after complete electrolysis of the resulting solution is: (in $\text{ L}$)

Which of the following statements is not correct?