Ethanol is used as a fuel additive. The complete combustion of ethanol yields: MCQ with Answer and Explanation

Ethanol is used as a fuel additive. The complete combustion of ethanol yields:
A. CO₂ and H₂O
B. CO and H₂O
C. CO and H₂
D. CO₂ and H₂
Answer: Option A
Solution (By JKSSB Mock Tests)
Complete combustion of ethanol: C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O + heat. In sufficient oxygen, carbon burns to CO₂, hydrogen to H₂O. Incomplete combustion (lack of O₂) produces CO and soot (C). Ethanol is a biofuel, reducing CO₂ emissions if derived from biomass. It has high octane number and is blended with petrol (gasohol). CO₂ is a greenhouse gas, but bioethanol is carbon-neutral over cycle.

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Correct Answer: Option C


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Correct Answer: Option A


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Correct Answer: Option B


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