C1 Alkenes, Cracking and Polymers

what is cracking
splitting up long chain hydrocarbons by passing vapour over a hot catalyst
1 of 42
3 products made from cracking
petrol, paraffin, ethene for plastics
2 of 42
what type of reaction is cracking
thermal decomposition
3 of 42
first step to cracking
heat the long chain hydrocarbon to vaporise it
4 of 42
second step to cracking
pass the vapour over a powdered catalyst
5 of 42
what is the temperature range used
400-700 degrees Celsius
6 of 42
what is the catalyst used
aluminium oxide
7 of 42
what happens on the surface of the catalyst
the long chain molecules split apart (crack) on the surface of the specks of catalyst
8 of 42
what are the products of cracking
alkanes and unsaturated hydrocarbons (alkenes)
9 of 42
what is created in the cracking of kerosene
octane and ethene
10 of 42
what is ethene
two C atoms, is for making plastics
11 of 42
what do alkenes have
C=C double bond (carbon double bond)
12 of 42
what are alkenes known as + why
unsaturated because they can make more bonds
13 of 42
how do they make more bonds
the double bond can open up, allowing the two carbon atoms to bond with other carbon atoms
14 of 42
what are first two alkenes
ethene, propene
15 of 42
what is the general formula for an alkene
16 of 42
what is the test for alkenes
adding the substance to bromine water, if alkene is present the browmine water will go from orange to COLOURLESS
17 of 42
why does the colour change
the double bond has opened up and formed bonds with the bromine
18 of 42
what does ethene + water make
19 of 42
what state must the water be in
steam, vaporised
20 of 42
what is this process called
21 of 42
what does there need to be for this process to occur
22 of 42
what is the process like
23 of 42
why will this change
ethene is made from crude oil which is a non renewable resource so making ethanol could become expensive
24 of 42
another way to produce ethanol
fermentation of sugar
25 of 42
2 differences of this process than with the fermentation of ethene
lower temperature needed and need simpler equipment
26 of 42
a pro for the raw material sugar being used instead of ethene
sugar is renewable
27 of 42
why is this a pro for countries which are poor with no oil reserves
they can grow the sugar
28 of 42
2 cons to fermentation of sugar
ethanol produced has a low concentration and needs to be purified
29 of 42
how are the majority of alkenes used
to make polymers
30 of 42
what is the process called
31 of 42
what happens in this process
joining together lots of monomers to form polymers
32 of 42
whats a monomer
small alkene molecule
33 of 42
whats a polymer
long chain molecules
34 of 42
what is needed in the polymerisation process
pressure and a catalyst
35 of 42
how do you name the polymer made
add poly, example: polyethene, polypropene
36 of 42
what affects the properties of the polymer
what its made from, temperature and pressure of polymerisation
37 of 42
how do properties affect the use
makes them suitable for various different uses
38 of 42
disadvantage to plastics
not biodegradable so dont rot
39 of 42
how do we resolve this
re-use and recycle them as much as possible
40 of 42
comparison of price between plastics and metals
plastics are cheaper
41 of 42
why might this change
as crude oil resources get used up the price of crude oil will rise
42 of 42

Other cards in this set

Card 2


3 products made from cracking


petrol, paraffin, ethene for plastics

Card 3


what type of reaction is cracking


Preview of the front of card 3

Card 4


first step to cracking


Preview of the front of card 4

Card 5


second step to cracking


Preview of the front of card 5
View more cards


No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Paints and oils resources »