What is coal gas a result of?

Coal gas is produced through the destructive distillation of bituminous coal. This process involves heating the coal in the absence of air, which causes it to break down chemically and releases various gases and vapors. These by-products are collected and can be processed further to create coal gas, which primarily consists of hydrogen, methane, carbon monoxide, and small amounts of other gases.

The significance of this process lies in its ability to convert solid coal into a gaseous form that can be used as a fuel source for heating, cooking, and lighting. This method was widely used before the advent of natural gas, making it an important part of the history of fuel gas systems. The other options such as combustion of natural gas, thermal cracking of hydrocarbons, or refining of fossil fuels refer to different processes that generate different products and are not directly related to the production of coal gas.