A Chemistry MCQ qn.
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Hi guys, i have this puzzling question which has been bugging my mind since the day i encountered it. Even after consulting my teacher my doubts are not cleared ==
Oh well anyways heres the qn:
Which compound, on combustion, never forms soot?
A. Carbon monoxide
B. Ethanol
C. Ethene
D. Methane
Well, my teacher and I both chose B but however the book's answer is A.
I was taught that ethanol is a clean fuel that always burn cleanly to form carbon dioxide and water only, no soot. But when carbon monoxide is burnt no soot is formed at all too right? The only product formed is carbon dioxide? So am i wrong? =/
Help is greatly appreciated =) -
Originally posted by InklingFeel:
Hi guys, i have this puzzling question which has been bugging my mind since the day i encountered it. Even after consulting my teacher my doubts are not cleared ==
Oh well anyways heres the qn:
Which compound, on combustion, never forms soot?
A. Carbon monoxide
B. Ethanol
C. Ethene
D. Methane
Well, my teacher and I both chose B but however the book's answer is A.
I was taught that ethanol is a clean fuel that always burn cleanly to form carbon dioxide and water only, no soot. But when carbon monoxide is burnt no soot is formed at all too right? The only product formed is carbon dioxide? So am i wrong? =/
Help is greatly appreciated =)
Flawed question. Combustion implies the reactant has no oxygen. CO reacting with O is called oxidation, not combustion.So yeah, both A and B are correct, coz the answer is arguably flawed. Happens very commonly (even in the actual 'O' and 'A' level exams).
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Oh i see. Thanks loads =)
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Originally posted by InklingFeel:
Oh i see. Thanks loads =)
You're totally welcome, InklingFeel!
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K, going out for dinner/supper liao. By the time I'm back, y'all koon liao. So make sure u guys have enough sleep, wake up refreshed for tmrw's exam paper, and makan enough breakfast so ur brain got glucose and can perform during the exam. Have fun!
