What happens to the carbon and hydrogen in a hydrocarbon during combustion?

During combustion, hydrocarbons react with oxygen to produce carbon dioxide and water. This process involves the combination of the carbon and hydrogen atoms in the hydrocarbon with oxygen atoms from the air. Specifically, the carbon from the hydrocarbon is oxidized to form carbon dioxide, and the hydrogen is also oxidized, forming water.

Oxidation is defined as a reaction in which a substance loses electrons. In the case of hydrocarbons, the carbon is transitioning from a lower oxidation state in the hydrocarbon to a higher oxidation state in carbon dioxide. Similarly, the hydrogen goes from a lower oxidation state to a higher state in water. This transformation demonstrates that both carbon and hydrogen undergo oxidation during the combustion process, leading to the release of energy in the form of heat and light.

The other options do not accurately describe the chemical changes that occur. For instance, stating that carbon and hydrogen remain unchanged or are reduced does not convey the actual chemical reaction taking place during combustion. Additionally, combustion does not produce solid carbon as a direct result, as the products primarily include gases like carbon dioxide and water vapor. Thus, the correct understanding of combustion is best captured by recognizing the oxidation of carbon and hydrogen.