cracking crude oil

Question 1

what does cracking mean?

Answer 1

splitting up long chain hydrocarbons

Question 2

why do we split up long chain hydrocarbons?

Answer 2

because long chain hydrocarbons are very thick e.g. tar and so they aren’t very useful so we turn the longer molecules into smaller more useful ones by a process called cracking.

Question 3

what type of reaction is cracking?

Answer 3

thermal decomposition- breaking down molecules by heating them

Question 4

what are the steps of cracking?

Answer 4

1. heat the long chain hydrocarbon to vaporise it
2. vapour is then passed down a powdered catalyst at 400-700 degrees c
3. aluminium is the powdered catalyst used
4. the long chain splits apart or ‘crack’

Question 5

what is produced by cracking?

Answer 5

shorter, more useful hydrocarbons

- mostly alkanes and alkenes

Question 6

write the equation of cracking

Answer 6

long chain hyrdocarbon——>shorter alkane+alkene
h h h h h h h h h h h h
h-c-c-c-c-c-c-c-h ——> h-c-c-c-h+ c=c
h h h h h h h h h h h h