Which of the following gases is a byproduct of combustion that poses health risks?

Carbon monoxide is a colorless, odorless gas that is produced during the incomplete combustion of fossil fuels and organic materials. Its formation occurs when there is not enough oxygen present for a fire to burn completely, leading to this toxic byproduct.

The significance of carbon monoxide lies in its ability to bind with hemoglobin in red blood cells much more effectively than oxygen does, which can lead to reduced oxygen transport throughout the body. This binding can result in symptoms ranging from headache and dizziness to life-threatening conditions in high concentrations. Because of these health risks, especially in enclosed or poorly ventilated spaces, carbon monoxide is recognized as a dangerous gas resulting from combustion processes.

In comparison, oxygen is essential for combustion and life, nitrogen makes up most of the atmosphere without being directly harmful, and hydrogen is not a combustion byproduct in the traditional sense and does not present the same toxic risks as carbon monoxide. Understanding the dangers of carbon monoxide helps in identifying and mitigating health risks associated with combustion activities.