Alkanes from crude oil

Question 1

What property does fractional distillation depend on?

Answer 1

Boiling points

Question 2

Why is Fractional distillation used ?

Answer 2

Crude oil contains different length hydrocarbons (alkanes) with different boiling points and this is used to seperate into fractions depending on boiling point

Question 3

Why are small HCs at the top and large at the bottom?

Answer 3

The longer the chain the larger the london forces so higher boiling point and as vapour rises parts of mixture condense. Shortest chains dont condense and turn to gas

Question 4

What is cracking?

Answer 4

Where heavier fractions are cracked to higher demand for shorter chain alkanes, always producing ethene, using the catalyst zeolite

Question 5

What is thermal cracking?

Answer 5

High temperature at 1000C, which always produce Alkenes for polymers

Question 6

What is Catalytic Cracking?

Answer 6

High temperatures at 450C using zeolite catalyst which produce aromatic hydrocarbons for fuel like Benezene rings.

Question 7

Whats the role Zeolite Catalysts?

Answer 7

It lower the tempertaure and pressure needed which lowers cost and speeds up reaction without being used up

Question 8

What is reforming?

Answer 8

where alkanes are reformed into branched or cyclic alkanes, reducing knocking and increasing engine efficiency, using platiunum catalyst