Chemistry - Other products from crude oil

HideShow resource information
What fractions are usually cracked?
Long chain fractions
1 of 35
Why are long chain fractions cracked?
It produces saturated hydrocarbons which are used as fuels and unsaturated hydrocarbons
2 of 35
How do we crack hydrocarbons?
By passing the vapours over a hot catalyst or by mixing them with steam and heating them to a very high temperature
3 of 35
What is the word equation for cracking decane?
decane -----------------------------> pentane + propene + ethene
4 of 35
What are alkenes?
Unsaturated hydrocarbons
5 of 35
What do unsaturated compounds contain?
At least one double bond between their carbon atoms
6 of 35
In a positive text for an unsaturated hydrocarbon, what colour does bromine water turn?
From orange to colourless
7 of 35
What is the general formula for alkenes?
CnH2n
8 of 35
How can Ethanol for industrial use as a fuel or solvent be made?
By cracking ethene with steam
9 of 35
What is the word equation for cracking ethene?
ethene + steam ethanol
10 of 35
What is the symbol equation for cracking ethene?
C2H4 + H2O C2H5OH
11 of 35
What is this reaction called?
Hydration
12 of 35
How can we make plastics?
Using the chemicals from crude oil
13 of 35
How can we make different types of plastics?
By using different monomers
14 of 35
What is the polymer made from ethene called?
Poly(ethene) or polythene
15 of 35
What are the properties of poly(ethene)?
Easy to shape, strong and transparent
16 of 35
What are some uses of poly(ethene)?
Plastic carrier bags, some drink bottles, dustbins, washing-up bowls and clingfilm
17 of 35
What is the polymer made from propane called?
Poly(propane)
18 of 35
What are the properties of poly(propane)?
Strong and tough
19 of 35
What are some of the uses of poly(propane)?
Carpets, milk crates and ropes
20 of 35
What happens when alkene molecules join together?
The double bond between the carbon atoms in each molecule 'opens up'. It is replaced by single bonds as thousands of molecules join together?
21 of 35
What is the reaction called when these molecules join together?
Polymerisation
22 of 35
What are the two types of poly(ethene)?
High density (HD) and low density (LD)
23 of 35
How is low density poly(ethene) made?
Using very high pressures and a trace of oxygen
24 of 35
How is high density poly(ethene) made?
Using a catalyst at 50 degrees and a slightly raised pressure
25 of 35
Why does low density poly(ethene) have a low density?
The polymer chains are randomly branched and they can't pack closely together
26 of 35
Why does high density poly(ethene) have a high density?
It is made up of straighter poly(ethene) chains and they can pack more closely together than branched chains
27 of 35
Why do thermosoftening polymer soften?
The forces between the polymer chains are weak. When we heat the polymer, the weak intermolecular forces are broken. The polymer becomes soft. When the polymer cools down, the intermolecular forces bring the polymer back together
28 of 35
Why don't thermosetting polymers soften?
The monomers make covalent bonds between the polymer chains when they are first heated in order to shape them. The covalent bonds stop the polymer from softening. The covalent 'cross links' between chains do not allow them to separate
29 of 35
What some new and useful polymer developments?
Fillings for teeth, softer lining for dentures, packaging materials, implants that can slowly release drugs into a patient
30 of 35
How do light-sensitive plasters work?
By using a light-sensitive polymer when the lower layer of the plaster is exposed to the light, the adhesive becomes less sticky
31 of 35
What are hydrogels?
Polymer chains with a few cross-linking units between chains
32 of 35
What are hydrogels used for?
Wound dressings and contact lenses
33 of 35
Why do shape memory polymers make stitching in awkward place easier
When it is used to stich a wound loosely, the temperature of the body makes the thread tighten and close the wound, applying just the right amount of force
34 of 35
What is a smart polymer?
One that changes in response to changes in its surroundings
35 of 35

Other cards in this set

Card 2

Front

Why are long chain fractions cracked?

Back

It produces saturated hydrocarbons which are used as fuels and unsaturated hydrocarbons

Card 3

Front

How do we crack hydrocarbons?

Back

Preview of the front of card 3

Card 4

Front

What is the word equation for cracking decane?

Back

Preview of the front of card 4

Card 5

Front

What are alkenes?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Crude oil, cracking and hydrocarbons resources »