In the context of proposals to the use of hydrogen- enriched CNG (H-CNG) as fuel for buses in public transport, consider the following statements:1. The main advantage of the use of H-CNG is the elimination of carbon monoxide emissions.2. H-CNG as fuel reduces carbon dioxide and hydrocarbon emissions.3. Hydrogen up to one-fifth by volume can be blended with CNG as fuel for buses.4. H-CNG makes the fuel less expensive than CNG.Which of the statements given above is/are correct?
✓ Correct answer: b) 2 and 3 only
ExplanationHydrogen-enriched CNG (H-CNG) is a blended gas.It is produced by mixing hydrogen with CNG.HCNG reduces emis- sions of CO up to 70% and engines can be calibrated to release lower amounts of NO. enables up to 5 % savings in fuel.It can be the first step towards the future Hydrogen economy.It gives better performance due to higher Octane rating of H2. Statement 1 is incorrect: HCNG doesn’t eliminate but reduces emissions of CO up to 70%.Statement 2 is correct: It can be used in place of gasoline, die- sel fuel and propane (C3H8) / LPG and its combustion produces fewer undesirable gases.Statement 3 is correct: The blending of hydrogen with CNG pro- vides a blended gas termed as HCNG.Also, the ideal Hydrogen concentration is close to 20 %.It can prove to be the ideal fuel for heavy-duty vehicles and applications with high loads.Statement 4 is incorrect: The current cost of Hydrogen is more than the cost of Natural Gas.So, HCNG’s cost is more than CNG.SUPER HINT When S2 says "Reduces", then, isn't S1's "Elimination of CO" an extreme phrase, hence S1 is more probable to be false,
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