AP Chemistrymediummcq1 pt
A hydrocarbon flame receives a restricted oxygen supply. Which toxic product can appear that would not form during complete combustion?
A.Carbon monoxide
B.Carbon dioxide
C.Hydrogen peroxide
D.Hydrogen gas
Explanation
Core Concept
With insufficient oxygen, carbon stops short of the +4 state it reaches in CO₂ and lands at +2 in carbon monoxide instead. Incomplete combustion therefore emits CO alongside water vapor. The gas is colorless and odorless yet binds hemoglobin tightly, which is why any flame burning in starved air is dangerous indoors.
Correct Answer
ACarbon monoxide
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