Calculate $$\Delta \mathrm{G}^{\circ}$$ for the cell:

$$\mathrm{Sn}_{(\mathrm{s})}\left|\mathrm{Sn}_{(\mathrm{1M})}^{+}\right|\left|\mathrm{Ag}_{(\mathrm{1M})}^{+}\right| \mathrm{Ag}_{(\mathrm{s})}$$ at $$25^{\circ} \mathrm{C}\left(\mathrm{E}_{\text {cell }}^{\circ}=0.90 \mathrm{~V}\right)$$

Calculate current in ampere required to deposit $$4.8 \mathrm{~g} ~\mathrm{Cu}$$ from it's salt solution in 30 minutes. [Molar mass of $$\mathrm{Cu}=63.5 \mathrm{~g} \mathrm{~mol}^{-1}$$ ]

Identify the gas produced due to reduction of $$\mathrm{NH}_4^{+}$$ ions at cathode during working of dry cell.

Which among the following statements is true for Galvanic cell?