Choose the correct representation of conductometric titration of benzoic acid vs sodium hydroxide.

For a spontaneous reaction,determine the values of $\Delta G^o$,equilibrium constant $K$,and $E^o_{cell}$ respectively.

In a fuel cell,methanol is used as fuel and oxygen gas is used as an oxidizer. The reaction is
$CH_3OH_{(l)} + \frac{3}{2} O_{2(g)} \rightarrow CO_{2(g)} + 2H_2O_{(l)}$
At $298 \ K$,standard Gibbs energies of formation for $CH_3OH_{(l)}$,$H_2O_{(l)}$,and $CO_{2(g)}$ are $-166.2$,$-237.2$,and $-394.4 \ kJ \ mol^{-1}$ respectively. If the standard enthalpy of combustion of methanol is $-726 \ kJ \ mol^{-1}$,the efficiency of the fuel cell will be .......... $\%$.

At $T(K)$,the molar conductivity of $0.04 \ M$ acetic acid is $7.8 \ S \ cm^2 \ mol^{-1}$. If the limiting molar conductivities of $H^{+}$ and $CH_3COO^{-}$ at $T(K)$ are $349$ and $41 \ S \ cm^2 \ mol^{-1}$ respectively,the dissociation constant of acetic acid is

Which one of the following statements is correct?

The number of incorrect statements from the following is:
$A.$ The electrical work that a reaction can perform at constant pressure and temperature is equal to the reaction Gibbs energy.
$B.$ $E_{cell}^0$ is dependent on the pressure.
$C.$ $\frac{dE_{cell}^0}{dT} = \frac{\Delta_{r}S^0}{nF}$.
$D.$ $A$ cell is operating reversibly if the cell potential is exactly balanced by an opposing source of potential difference.