Which gases are commonly found in products of combustion?

Products of combustion primarily include gases that result from the chemical reaction of fuel with oxygen during burning. In a typical combustion process involving hydrocarbons, carbon dioxide (CO₂), nitrogen (N₂), and water vapor (H₂O) are among the key products. Although oxygen (O₂) may be present in small amounts, it is generally consumed in the combustion reaction rather than being present in significant amounts in the exhaust.

The inclusion of carbon dioxide in the list directly relates to complete combustion, where carbon in the fuel reacts with oxygen to form CO₂. Nitrogen is a significant component of the air used in combustion, though it does not participate in the combustion process and is often present in the exhaust gases due to the high percentage of atmospheric nitrogen that is drawn into the combustion chamber. While hydrogen is a component of many fuels, it is not typically a direct product of combustion in gaseous form.

The other choices include incorrect or less representative combinations of combustion products. Hydrogen, for instance, is not a typical product of combustion and does not appear in significant quantities as a combustion byproduct. Sulfur dioxide (SO₂) and carbon monoxide (CO) may form under specific conditions but do not represent the most common products of combustion when hydrocarbons