What is required to ignite natural gas?

To ignite natural gas, a mixture of gas and air is necessary. This is because natural gas, primarily composed of methane, requires oxygen to combust. When natural gas mixes with air, it creates an explosive mixture that can be ignited by a spark or flame. The proportions of gas and air are critical; typically, a specific ratio must be achieved for ignition to occur, known as the Lower Explosive Limit (LEL) and Upper Explosive Limit (UEL).

The other options involve combinations that do not facilitate combustion in the same effective manner. For instance, a mixture of gas and water does not support combustion since water is not flammable. Similarly, mixtures involving solid fuels or oil do not provide the necessary oxygen required for natural gas ignition and would instead involve different combustion processes altogether. Thus, the ignition of natural gas hinges strictly on the right combination of gas and air.