G2 Gas Fitter Practice Exam

What are the products of complete combustion of natural gas in the air?

1. Carbon monoxide, soot, and heat

2. Carbon dioxide, water vapour, and heat

3. Hydrogen, carbon dioxide, and ash

4. Carbon dioxide, steam, and noise

The correct answer is: Carbon dioxide, water vapour, and heat

The products of complete combustion of natural gas primarily include carbon dioxide, water vapor, and heat. When natural gas, which mainly consists of methane (CH₄), burns in the presence of sufficient oxygen, it undergoes a chemical reaction where its carbon and hydrogen combine with oxygen to produce carbon dioxide (CO₂) and water (H₂O), while releasing energy in the form of heat. During complete combustion, all the carbon in the methane is converted into carbon dioxide, and all the hydrogen is converted into water. This process is efficient because it maximizes the use of fuel and minimizes the release of harmful byproducts such as carbon monoxide (produced during incomplete combustion) or soot (particulate matter). Understanding the products of combustion is essential for gas fitters, as it informs safety practices and compliance with environmental regulations, helping to reduce emissions and promote cleaner burning procedures. This makes the knowledge of complete combustion crucial for ensuring efficient and safe operations within the field.