The important characteristics of petroleum are summarized below. For a recent illustration of the importance of petroleum in international economics and politics, click here . For a brief history of petroleum, click here .
Petroleum is a complex liquid mixture that contains hundreds of compounds.
Compounds containing only carbon and hydrogen in their molecular structure are desirable because they are responsible for the high heating value of petroleum. At the other extreme, compounds containing sulfur and nitrogen are bad news because during combustion they are converted to sulfur dioxide and nitrogen oxides, which are the precursors to acid rain . Let's follow the itinerary of petroleum from its reservoir in the Earth's crust to its final destination. Petroleum is not distributed democratically around the globe. Millions of years ago, as it was formed from decaying plant and animal material, particularly rich deposits were accumulated in the Persian Gulf area.