Based on the redox equations;
The emf of the cell, E°cell of the cells formed from the half-reactions is 0.21 V
Reducing agents are substances which donates electrons and are oxidized in a redox reaction.
Oxidizing agents are substances which accept electrons and are reduced in a redox reaction.
From the given the redox equations:
a) O_2(g) + NO(g) + H_2O(l) → NO_3^{-}(aq) + H^{+}(aq)
b) CrO_4^{2-}(aq) + H_2O(l) + Cu(s) → Cr(OH)_3(s) + Cu(OH)_2(s) + OH^{-}(aq)
2. The emf of the cell, E°cell = E°red - E°oxi
In the cell, copper is reduced while tin is oxidized.
E°cell = (0.34 - 0.13) V
E°cell = 0.21 V
Therefore, the emf of the cell, E°cell is 0.21 V
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