Burning Carbon Fuels

This quiz is concerned with the burning of the three fossil fuels and some of the problems this causes. Coal is mainly carbon and tar, which is a thick, sticky hydrocarbon. Oil is made from a mixture of liquid hydrocarbons (predominantly members of the alkane family), whilst natural gas is essentially the alkane with the smallest molecule - methane. Since these formed from living organisms, there are traces of the element sulfur (and others too) that have come from their proteins.

When anything burns, it is an oxidation reaction. In other words, the elements of the material being burnt become oxides. So when hydrocarbons burn, the hydrogen becomes water and the carbon becomes carbon dioxide (or carbon monoxide when incomplete cumbustion takes place). Since coal and oil contain a lot of carbon in their compounds, they produce a lot of carbon dioxide and carbon monoxide. Carbon monoxide is toxic, it prevents the blood from carrying oxygen. Carbon dioxide is a greenhouse gas and the vast majority of scientists believe that the increase of carbon dioxide in the air is a significant cause of global warming.

There is another kind of pollution caused by burning fossil fuels. When the sulfur burns, it forms acidic oxides causing acid rain. This problem has been reduced in many developed countries as petroleum companies remove as much of the sulfur as they can from the fuels they sell.