Which of the following gases is primarily expelled from a gas turbine during operation?

The primary gas expelled from a gas turbine during operation is carbon dioxide. This results from the combustion of fuel, where hydrocarbon fuels are burned in the presence of oxygen, leading to a chemical reaction that produces carbon dioxide and water vapor as the main byproducts. As the gas turbine operates, the high-temperature gases produced during combustion expand and exit the turbine, and these gases are primarily composed of carbon dioxide among other components.

While water vapor is also a significant byproduct of combustion, carbon dioxide is more abundant in the gaseous emissions of a gas turbine. Oxygen is consumed during the combustion process rather than being expelled, and nitrogen, while present in the air used for combustion, does not react and is typically released unchanged in the exhaust but in lesser quantities than carbon dioxide. Thus, in terms of overall volume and concentration, carbon dioxide is the predominant gas expelled from the turbine.