CBSE Class 12 · 2011 · All India Compartment · Redox Reactions and ElectrochemistryShort Answer

Give an example of a fuel cell and write the cathode and anode reactions for it.

Answer: H₂–O₂ fuel cell. Anode: 2H₂+4OH⁻→4H₂O+4e⁻; cathode: O₂+2H₂O+4e⁻→4OH⁻.

Solution

Example: the hydrogen–oxygen fuel cell (basic medium).
Anode:

2 H_{2} (g) + 4O H^{-} (aq) ⟶ 4 H_{2} O (l) + 4 e^{-}

Cathode:

O_{2} (g) + 2 H_{2} O (l) + 4 e^{-} ⟶ 4O H^{-} (aq)

CBSE Class 12 Board · 2011 · All India Compartment · Subjective