In a fuel cell methanol is used as fuel and oxygen gas is used as an oxidizer. The reaction is
CH₃OH(l) + 3/2O₂ $$\to$$ CO₂ (g) + 2H₂O (l)
At 298K standard Gibb’s energies of formation for CH₃OH(l), H₂O(l) and CO₂ (g) are -166.2, -237.2 and -394.4 kJ mol⁻¹ respectively. If standard enthalpy of combustion of methanol is -726 kJ mol⁻¹, efficiency of the fuel cell will be

Given $$E_{C{r^{3 + }}/Cr}^o$$ = -0.72 V; $$E_{Fe^{2+}/Fe}^o$$ = -0.42V, The potential for the cell Cr | Cr³⁺ (0.1M) || Fe²⁺ (0.01 M) | Fe is

The equivalent conductances of two strong electrolytes at infinite dilution in H₂O (where ions move freely through a solution) at 25^oC are given below:
$$ \wedge _{C{H_3}COONa}^o$$ = 91.0 S cm²/equiv
$$ \wedge _{HCl}^o$$ = 426.2 S cm²/equiv
What additional information/quantity one needs to calculate $$ \wedge ^o$$ of an aqueous solution of acetic acid?

The cell, Zn | Zn²⁺ (1M) || Cu²⁺ (1M) | Cu($$E_{cell}^o$$ = 1.10V) was allowed to be completely discharged at 298 K. The relative concentration of Zn²⁺ to Cu²⁺ $$\left[ {{{\left[ {Z{n^{2 + }}} \right]} \over {\left[ {C{u^{2 + }}} \right]}}} \right]$$ is