Gas Heat ESCO Practice Exam

Which of the following must be present for combustion to occur?

1. Air, fuel, ignition (heat)

2. Fuel, nitrogen, oxygen

3. Heat, carbon dioxide, fuel

4. Ignition (heat), nitrogen, fuel

The correct answer is: Air, fuel, ignition (heat)

For combustion to occur, three essential elements must be present: air, fuel, and ignition (heat). - Air is necessary because it provides the oxygen needed for the combustion process to take place. - Fuel is essential as it provides the material that will be burned during combustion. - Ignition, often in the form of heat, is required to raise the temperature of the fuel to its ignition point, initiating the combustion reaction. Therefore, among the options provided, choice A is the correct answer as it includes all three essential elements needed for combustion to occur. The other options lack one or more of these key components, making them incorrect.