Justin C. answered • 01/31/21
Chemical Engineer that LOVES teaching chemistry (5+ years)
Hello Raneem,
Fossil fuels include a long list of hydrocarbons (molecules made of hydrogen and carbon atoms). They come in solid form (coal), gaseous form (natural gas or methane, propane), and liquid form (jet fuel, gasoline or octane, hexane, etc.). Essentially, they are a chains of carbon atoms of varying lengths (1 being methane, all the way to the largest ever made with 1134 carbon atoms).
Fossil fuels are generally generated by decomposition of dead organic material that has been buried under a layer of Earth. In essence, they are a remnant of life that used to live on this Earth, hence the name FOSSIL fuels. Decomposition creates them by breaking down the cells that make up life, which happen to be made up of massive molecules with hundreds and thousands of carbon atoms. When those molecules are broken up, they turn to smaller molecules like the ones mentioned above.
Fortunately (or unfortunately) for us, they have an extremely large energy density. This energy is most commonly released as heat by burning them. All it takes to burn them is a little bit of energy to ignite them (a spark) and a bunch of oxygen. However, the products of these reactions are the things that are bringing about rapid climate change in our atmosphere: carbon monoxide and carbon dioxide.
After taking millions and millions of years to build up, humans have fairly quickly released a significant amount of the energy stored in those fossil fuels in just a few thousand years. While we (literally our bodies) and the animals and plants we share this Earth with may one day contribute to a new reserve of fossil fuels, we will likely deplete all of the current ones millions of years before that happens. Thus, we need to commit to switching over to alternative sources of energy relatively quickly.
Hopefully you can find what you were looking for somewhere in here. And, if you ever need any help, feel free to reach out. Cheers!
Justin
