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Flashcards in cracking hydrocarbons Deck (13)
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1
Q

what is cracking

A

longer chain molecules can be broken down into shorter more useful hydrocarbons

2
Q

two main methods of cracking are

A

steam cracking and catalytic cracking

3
Q

during steam cracking:

A
  • hydrocarbons are mixed with steam

- heated to 850°

4
Q

during catalytic cracking:

A
  • hydrocarbons are heated until they vaporise
  • vapour is passed over a hot aluminium oxide catalyst
  • a thermal decomposition reaction then takes place
5
Q

thermal cracking uses

A

high temp and pressure

6
Q

catalytic cracking uses

A

low temp and pressure using catalyst

7
Q

SSS for bromine water

A
  • single bond (alkane)
  • saturate
  • satsuma colour, orange to colourless
8
Q

what does saturated mean

A

lots of hydrogens

9
Q

formula for alkene

A

CnH2n

10
Q

what does an alkane contain

A

single bonds

think of how alkAne ((a)) comes first in alphabet, so it’s single whereas as alkEne ((e)) comes later

11
Q

what are alkane used for

A

fuels

12
Q

what are alkenes used for

A

polymers and manufacture of plastics

13
Q

alkenes have

A

double bonds