What are the components of flue gases produced from the complete combustion of natural gas?

The correct choice highlights the comprehensive nature of flue gases that result from the complete combustion of natural gas. When natural gas, primarily composed of methane (CH4), is burned in the presence of sufficient oxygen, it undergoes a chemical reaction that produces several key components.

During complete combustion, the methane reacts with oxygen to produce carbon dioxide and water vapor. Carbon dioxide is a primary byproduct, as it results from the carbon in the natural gas fully oxidizing. Water vapor is generated from the hydrogen atoms in the methane combining with oxygen during combustion. In addition to these primary products, nitrogen is often included in the flue gas composition as it is a major component of the air used for combustion. Although nitrogen does not participate in the combustion reaction, it is present in the flue gases due to being an atmospheric constituent.

Moreover, complete combustion does generate heat and light, which is inherent to the combustion process itself. While excess air is noted here, it primarily refers to ensuring there is enough oxygen for complete combustion, sometimes resulting in oxygen being present in the exhaust when combustion is not perfectly efficient.

Thus, the answer encapsulates the essential products of complete combustion along with the contextual components that may be present in the combustion environment, making it the