Which substance is a primary source of hydrocarbons? a. cottonb. metalsc. petroleum d. soil

The answer is: C. Petroleum.

Petroleum consists of hydrocarbons with between four and twenty carbon atoms.

Petroleum is a mixture of many different hydrocarbons: alkanes (paraffins), cycloalkanes and alkenes (olefins).

Petroleum is used primarily as a fuel in combustion engines.

Most motor oils are made from a heavier, thicker petroleum hydrocarbons.

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