My answers--->Part4

Constituents of petroleum:
:petroleum are said to be made of carbon, sulphur and lead.
:carbon is present in major quantity. Sulphur content is negligible.Lead is present in low quantity.(0.05%)--{This is my own data).
The constituents of the petroleum are extracted in a Fractional distillation column.
In this column, the components are separated based on the boiling point of the substances.
catalytic cracking is a process of breaking of heavier hydrocarbons into lower value hydrocarbons.
the various components of petroleum are separated based on the difference in the boiling point.........
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here ends my story.