Read the following passage given below and answer the question.
Production of electricity by thermal plants is not very efficient method. It is now possible to make cells in which reactants are fed continuously to the electrodes and products are also removed continuously. One of the most successful fuel cells is hydrogen fuel cell.
Which of the following statement is correct regarding hydrogen fuel cells?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → The electricity production in fuel cells is higher than that in thermal plants
A fuel cell converts the energy of combustion of a fuel directly into electrical energy, so it avoids the heat → steam → turbine steps of a thermal plant, where much energy is lost as heat. Fuel cells work with an efficiency of about 70%, compared with about 40% for thermal plants. So more electricity is produced from the same amount of fuel.
Option (1) This cell used the reaction between hydrogen and nitrogen to form ammonia — Incorrect. The cell uses the reaction of hydrogen with oxygen to form water; no ammonia is formed.
\( \displaystyle \ce{2H2(g) + O2(g) -> 2H2O(l)} \)
Option (2) Catalysts such as finely divided platinum or palladium metal do not have any effect on the rate of electrode reactions — Incorrect. Finely divided platinum or palladium is put into the electrodes to increase the rate of the electrode reactions.
Option (4) The cell can run even when reactant supply stops — Incorrect. The cell runs only as long as the reactants are supplied. It stops when the supply of \( \ce{H2} \) and \( \ce{O2} \) stops.
NCERT (2026-27 edition):
Fuel Cells – “… The cell runs continuously as long as the reactants are supplied. Fuel cells produce electricity with an efficiency of about 70 % compared to thermal plants whose efficiency is about 40%.”