Which of the following acts as an oxidising agent in a hydrogen-oxygen fuel cell?

Which one of the following statements is true for a standard electrochemical cell involving $H_2$ and $Cu$ electrodes?

Which of the following changes occurs during the discharging of a lead accumulator?

The work done in a galvanic cell is equal to which of the following?

In batteries and fuel cells,which energy is converted into which energy?

At $25^{\circ} C$,the molar conductance at infinite dilution for the strong electrolytes $NaOH$,$NaCl$ and $BaCl_{2}$ are $248 \times 10^{-4}$,$126 \times 10^{-4}$ and $280 \times 10^{-4} \ S \ m^{2} \ mol^{-1}$ respectively. $\lambda_{m}^{o} Ba(OH)_{2}$ in $S \ m^{2} \ mol^{-1}$ is