Question

Write the equation for the half reaction that occurs at the cathode in a hydrogen fuel cell under alkaline conditions a) O₂(g)+2H⁻ (aq)+2e⁻ →H₂O(l)

b) O₂(g)+4H⁻(aq)+4e ⁻→2H₂O(l)

c) 2H₂O(l)→O₂(g)+4H⁻ (aq)+4e⁻


d) H₂O(l)+O₂(g)+4e⁻→4OH ⁻(aq)

Answer 1

The correct half-reaction occurring at the cathode under alkaline conditions in a hydrogen fuel cell is O2(g) + 2H2O(l) + 4e- → 4OH-(aq). In a galvanic cell, the cathode is positive and the anode is negative.

Step-by-step explanation:

The student's question involves writing the equation for the half-reaction that occurs at the cathode in a hydrogen fuel cell under alkaline conditions. The correct half-reaction for the oxygen reduction at the cathode under alkaline conditions is:

O2(g) + 2H2O(l) + 4e- → 4OH-(aq)

For a typical hydrogen fuel cell, the anode reaction would involve the oxidation of hydrogen:

2H2(g) → 4H+(aq) + 4e-

In a galvanic cell, the electrode at which reduction occurs is the cathode, which is positive, and the electrode at which oxidation occurs is the anode, which is negative.