CRUDE OIL

MILLIONS OF YEARS AGO, LARGE AMOUNTS OF DEAD MICRO-ORGANISMS ACCUMULATED AT RIVER MOUTHS AND ON LAKES.

THE MICRO-ORGANISMS DID NOT COMPLETELY DECOMPOSE BECAUSE THERE WAS NOT 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

HYDROCARBON MOLECULES ARE HYDROGEN ATOMS AND CARBON ATOMS LINKED TOGETHER IN CHAINS OF DIFFERENT LENGTHS.

FOR EXAMPLE,OCTANE HAS A LENGTH OF EIGHT CARBON ATOMS