Question

What are fuel cells? Write reaction of a hydrogen-oxygen fuel cell. Write two advantages of the use of a hydrogen-oxygen fuel cell.

Answer 1

Fuel cell is an electrochemical cell in which chemical energy of fuel is directly converted into electrical energy. It converts the energy from the combustion of fuels such as H2, CO, CH4 etc directly into the electrical energy.

Fuel cell is designed in such a way that the materials to be oxidised at anode and reduced at cathode are stored outside the electrodes , so as to maintain a constant supply. One of the most successful fuel cell is the H2-O2 fuel cell. The H2-O2 fuel cell consists of a porous electrodes filled with catalysts like Pt,Ag etc. 

Answer 2

Hydrogen fuel is a zero-emission fuel when burned with oxygen. It can be used in electrochemical cells or internal combustion engines to power vehicles or electric devices. It has begun to be used in commercial fuel cell vehicles such as passenger cars, and has been used in fuel cell buses for many years.

Advantages

1. It is readily available.

As mentioned earlier, hydrogen is a basic earth element and it’s very abundant. However, it takes a whole lot of time to separate hydrogen gas from its companion substances.  

2. It doesn’t produce harmful emissions.

When hydrogen is burned, it doesn’t emit harmful substances. Basically, it reacts to oxygen without burning and the energy it releases can be used to generate electricity used to drive an electric motor.