With reference to ‘fuel cells’ in which hydrogen- rich fuel and oxygen are used to generate electricity, consider the following statements:1. If pure hydrogen is used as a fuel, the fuel cell emits heat and water as by-products.2. Fuel cells can be used for powering buildings and not for small devices like laptop computers.3. Fuel cells produce electricity in the form of Alternating Current (AC).Which of the statements given above is/are correct?
✓ Correct answer: a) 1 only
ExplanationStatement 1 is correct: In a hydrogen fuel cell, hydrogen (H₂) reacts with oxygen (O₂) from the air in an electrochemical reaction.This process generates electricity along with water (H₂O) and heat as by-products.Since no harmful emissions are released, this is considered a clean energy technology.Statement 2 is incorrect: Fuel cells are highly adaptable and can be designed for various applications, ranging from powering large buildings and vehicles to smaller portable devices such as laptops.Proton Exchange Membrane Fuel Cells (PEMFCs) are particularly suitable for portable devices due to their compact size and efficiency.Statement 3 is incorrect: Fuel cells generate electricity in the form of Direct Current (DC).However, many applications require Alternating Current (AC) to operate and thus an inverter is typically used to convert the DC produced by the fuel cell into AC.175
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