C1.5 Other substances from crude oil

Question 1

In what process are long-chain hydrocarbon molecules split into smaller ones?

Answer 1

Cracking

Question 2

Products of cracking

Answer 2

Petrol, paraffin and ethene

Question 3

What are petrol and paraffin useful for?

Answer 3

Fuels

Question 4

What is ethene useful for?

Answer 4

Plastics

Question 5

What is the process of cracking?

Answer 5

1. Heat the hydrocarbons to vaporise them
2. Pass the vapour over a powdered catalyst at a temperature of around 400-700 degrees
3. The hydrocarbons split apart on the surface of the catalyst

Question 6

Which catalyst is used in cracking?

Answer 6

Aluminium Oxide

Question 7

What are products of cracking?

Answer 7

Alkanes and alkenes (unsaturated hydrocarbons)

Question 8

What is the general formula of an alkene?

Answer 8

CnH2n

Question 9

Name a long-chain hydrocarbon molecule

Answer 9

Kerosene

Question 10

Name a shorter Alkane molecule

Answer 10

Octane

Question 11

Name two Alkenes

Answer 11

Ethene and propene

Question 12

Name a difference between Alkenes and Alkanes

Answer 12

Alkenes have a double bond between the carbon atoms

Question 13

Why are Alkenes unsaturated?

Answer 13

They can make more bonds, the double bond can open allowing the carbon atoms to bond with other atoms

Question 14

What is one of the general representations of an alkene?

Answer 14

C3H6

Question 15

How can you test for an alkene?

Answer 15

Adding bromine water. The bromine water will decolourise if an alkene is present. It will turn from orange to colourless

Question 16

How is ethanol produced from ethene?

Answer 16

Ethene is hydrated by steam (H2O) in the presence of a catalyst. It’s cheap but non-renewable

Question 17

How else can ethanol be produced?

Answer 17

From renewable sources through fermentation with yeast

Question 18

Word equation for fermentation

Answer 18

Sugar => Carbon Dioxide + Ethanol

Question 19

What is the material used in fermentation?

Answer 19

Sugar which is converted into Ethanol using yeast

Question 20

Why is fermentation a good method for producing ethanol?

Answer 20

It is a renewable source and can be used as quite a cheap fuel

Question 21

What are the disadvantages of fermentation?

Answer 21

The ethanol produced isn’t very concentrated so it needs to be distilled to increase its strength. It also needs to be purified

Question 22

What can Alkenes be used to make?

Answer 22

Polymers

Question 23

What is polymerisation?

Answer 23

The joining of many small molecules (monomers) to form very large molecules (polymers)

Question 24

What are light, stretchable polymers used for?

Answer 24

Making plastic bags

Question 25

What are elastic polymer fibres used for?

Answer 25

Making lycra fibre for tights

Question 26

What other products are polymers used for?

Answer 26

Waterproof coatings for fabrics, dental polymers are used in resin tooth fillings, wound dressings, packaging, smart materials e.g. memory foam

Question 27

Why are polymers hard to get rid of?

Answer 27

The are not biodegradable so they do not rot which leads to problems with waste disposal

Question 28

What new products are being developed with polymers?

Answer 28

Plastic bags made of polymers and cornstarch which break down more easily and biodegradable plastics also made from cornstarch

Question 29

Why will polymers become more expensive and rarer?

Answer 29

Crude oil resources will get used up and the price of crude oil will increase