Which product is not typically produced by incomplete combustion of a hydrocarbon?

Which product is not typically produced by incomplete combustion of a hydrocarbon?

• A. CO2
• B. CO
• C. C
• D. H2O

Answer: (A)

The key idea is how the amount of oxygen available during combustion determines what products form. With limited oxygen, carbon in the hydrocarbon isn’t fully oxidized, so you typically get carbon monoxide or even solid carbon, while hydrogen tends to form water. Water can still form in incomplete combustion because some oxygen is present to oxidize hydrogen. Carbon dioxide, on the other hand, is the fully oxidized form of carbon and appears mainly when combustion goes to completion with plenty of oxygen. Since incomplete combustion lacks enough oxygen to push all the carbon to CO2, carbon dioxide is not typically produced in that scenario.

The key idea is how the amount of oxygen available during combustion determines what products form. With limited oxygen, carbon in the hydrocarbon isn’t fully oxidized, so you typically get carbon monoxide or even solid carbon, while hydrogen tends to form water. Water can still form in incomplete combustion because some oxygen is present to oxidize hydrogen. Carbon dioxide, on the other hand, is the fully oxidized form of carbon and appears mainly when combustion goes to completion with plenty of oxygen. Since incomplete combustion lacks enough oxygen to push all the carbon to CO2, carbon dioxide is not typically produced in that scenario.