Final answer:
An oxidizer, typically oxygen from the air, is mixed with fuel in a burner prior to combustion. Air serves as the common source of oxygen necessary for the combustion reaction, facilitating the burning process and the release of energy.
Step-by-step explanation:
During combustion, an oxidizer is mixed with fuel in the burner prior to combustion. The oxidizer, often oxygen from the air, is essential for combustion to occur, as it supports the chemical processes that happen during a fire. According to Smokeybear.com, oxygen is one of the three elements needed for a fire to take place, along with heat and fuel. Air, which contains about 21 percent oxygen, is the common oxidizer provided to the furnace to initiate and maintain the combustion process. In a furnace, preheated air is blown in, which oxidizes the coke, resulting in the release of heat and the production of carbon dioxide.