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What Is Crude Oil?

When answering the question "What is crude oil?" the usual response is to describe the physical characteristics of the substance. Crude oil, also known as petroleum, is the name for the substance as it comes out of the ground. It is a fossil fuel, which means that crude oil is formed of organic material from long ago plants and creatures whose remains were compressed and heated by the pressure of sediment above. The heat and pressure cause a change in the molecular structure to form hydrocarbons.

Hydrocarbons are varying length strings of hydrogen and carbon atoms. The different shape and sizes of hydrocarbons are what make them so exciting to chemists who have managed to unlock a multitude of products which can be made from crude oil. Products as widely ranging as fuel oil, wax, and plastics all come from working with the hydrocarbons found in crude oil.

To answer the question "What is crude oil?" one might respond "energy". Most of products derived from crude oil have the capability of giving off energy. These products include gasoline, diesel, kerosene and others.

Others would answer the question "What is crude oil?" by answering "the driving force of the industrial society" and it's true that society in most of the civilized world runs on crude oil.

For many years after the discovery of the first crude oil deposits in Western Pennsylvania, most people did not know what to do with the product. The Seneca Indians of the area used it for body paint and to relieve symptoms of diseases ranging from consumption to gout. Early settlers also were uncertain about the value of what was called Seneca Oil. The product acquired the term "snake oil" as a derogatory term.

It is apparent though that prehistoric peoples in the area recognized and used the substance we now call crude oil. Some even used it for lighting.

Chemists today take the crude oil and initially distill it to break it down into major groupings. They then split the hydrocarbon molecules, rearrange them and recombine them in various ways. Initially, the products of distillation range from very heavy oil suitable for asphalt, and paraffin wax, successively the lighter products are drawn off during the fractioning process including light oil, diesel, kerosene, naphtha, gasoline and the lighter than air volatile gases.

From the paraffin grouping comes products such as wax and lubricants; naphtha with such processes as catalyst cracking is able to break down the long complicated strings of hydrocarbon molecules and to rearrange them or recombine them into shorter strings chemically. The gases provide such products as methane which is the shortest and simplest hydrocarbon molecule.

Crude oil is considered conventional oil today, but non-conventional oil such as oil sands, shale oil and bitumen deposits can also be mined, chemically processed and thereafter treated in much the same way as crude oil is refined.
As crude oil deposits continue to be found and extraction methods are more sophisticated, one must still keep in mind that there is a finite supply of crude oil. One final answer to the question of "What is crude oil?" is "An endangered species."