what are fuel cells class 12

Fuel Cells

Fuel cells are electrochemical cells that convert the chemical energy of a fuel directly into electrical energy. In Class 12 Chemistry, they are usually explained with the hydrogen-oxygen fuel cell as the main example.

Simple definition

A fuel cell is a galvanic cell that produces electricity from a continuous supply of fuel and oxygen. Unlike a battery, it does not get “used up” quickly as long as the reactants keep flowing.

How it works

• Hydrogen is oxidized at the anode.
• Oxygen is reduced at the cathode.
• The movement of electrons through the external circuit gives electric current.

Main reaction

For the hydrogen-oxygen fuel cell, the overall reaction is:
2H₂(g) + O₂(g) → 2H₂O(l)

Why it matters

Fuel cells are important because they are efficient and produce less pollution, so they are used in spacecraft, vehicles, and some power systems.

Exam-ready line

Fuel cells are devices that convert the energy of combustion of fuels directly into electrical energy by redox reactions.

TL;DR: Fuel cells are like clean electricity generators that use fuel and oxygen continuously to make power, and the hydrogen-oxygen fuel cell is the standard Class 12 example.