CRUDE OIL

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11.3 CRUDE OIL

            Origin

             Millions of years ago large amounts of dead micro-organisms acumulated at rivers mouths and on lakes. 

             The micro-organisms didn´t decompose because there wasn´t enough oxygen in the water.

             Later, sediments covered them.

             Crude oil comes from that organic matter.Crude oil is a mixture of hydrocarbon molecules, for example "octane"

             (C8H18).

             Hydrocarbon molecule are hydrogen atoms and carbon atoms linked