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प्रश्न
Write cathode and anode reaction in a fuel cell.
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उत्तर
Cell reactions in a fuel cell:
Oxidation at the anode (-):
Oxidation of hydrogen gas to water occurs at the anode.
2H2(g) + 4OH-(aq) →4H2O(l) + 4e-
Reduction at the cathode (+):
Reduction of oxygen gas to OH ions occurs at the cathode.
O2(g) + 2H2O(l) + 4e- → 4OH-(aq)
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संबंधित प्रश्न
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Fuel cell
E°cell for the given redox reaction is 2.71 V
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Calculate Ecell for the reaction. Write the direction of flow of current when an external opposite potential applied is
(i) less than 2.71 V and
(ii) greater than 2.71 V
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(b) \[\ce{2H2O (1) -> O2 (g) + 4H^{+} (aq) + 4e^{-}; E^Θ_{cell} = 1.23V}\]
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Match the terms given in Column I with the units given in Column II.
| Column I | Column II |
| (i) Λm | (a) S cm-¹ |
| (ii) ECell | (b) m-¹ |
| (iii) K | (c) S cm2 mol-¹ |
| (iv) G* | (d) V |
Match the terms given in Column I with the items given in Column II.
| Column I | Column II |
| (i) Λm | (a) intensive property |
| (ii) ECell | (b) depends on number of ions/volume |
| (iii) K | (c) extensive property |
| (iv) ∆rGCell | (d) increases with dilution |
Match the items of Column I and Column II.
| Column I | Column II |
| (i) K | (a) I × t |
| (ii) Λm | (b) `Λ_m/Λ_m^0` |
| (iii) α | (c) `K/c` |
| (iv) Q | (d) `G^∗/R` |
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Two metal plates or wires through which the current enters and leaves the electrolytic cell.
