Question

Explain how electricity is produced using a hydrogen fuel cell.

Answer 1

Hydrogen fuel cell is silimar to traditional electrolytic cell in many manners. Fuel cell is composed of anode and cathode and both are separated by a proton exchange membrane. The hydrogen is passed through a metallic anode which is a good hygrogen adsorbent usually platinum. And oxygen is passed through cathode.

The hydrogen is oxidixed at anode as follows:

H₂ 2 H⁺ + 2 e^-

^{The electrons thus produced pass through external circuit to cathode thus generating electricity}

And the hydrogen ion is diffused through a proton exchange membrane to cathode

At cathode then hydrogen atom and eletrons from external circuit combine with oxygen to give water as follows:

O₂ + 4 e^- + 4 H⁺ 2 H₂O

The potential difference created at standard conditions by these reactions is 1.23V which is responsible for electric current.

The energy of combustion of hydrogen via electrolytic pathway is converted into electric energy in a fuel cell.