Final answer:
Complete combustion releases more energy compared to incomplete combustion because it produces carbon dioxide and water, which release more heat.
Step-by-step explanation:
Complete combustion releases more energy compared to incomplete combustion.
During complete combustion, a fuel reacts with oxygen to produce carbon dioxide and water. This reaction is exothermic, meaning it releases energy in the form of heat.
In incomplete combustion, a fuel reacts with a limited supply of oxygen, resulting in the production of carbon monoxide and/or soot. This reaction is also exothermic, but less energy is released compared to complete combustion.