C1.5 Making Crude Oil Useful

Question 1

Describe the three steps of cracking

Answer 1

• The hydrocarbon is vaporised by heating it
• the vapour passes over a catalyst (aluminium oxide) at a very high temperature (400-700oC)
• The hydrocarbon splits apart

Question 2

What two products are produced by cracking an alkane.

Answer 2

An alkane and an alkene

Question 3

Describe the test for alkenes.

Answer 3

• React with bromine water

- Bromine water turns colourless

Question 4

What does the term saturated mean?

Answer 4

Single bonds only

Question 5

What does the term unsaturated mean?

Answer 5

Has one or more double bond(s)

Question 6

Describe how ethanol is produced from ethene

Answer 6

Reacting with steam

in the presence of a catalyst

Question 7

Name an advantage and disadvantage of using ethene to produce ethanol.

Answer 7

Advantage - ethanol is the only product.

Disadvantage - ethene comes from crude oil, which is non-renewable.

Question 8

Write the word equation for the fermentation of sugar to produce ethanol

Answer 8

Sugar –> ethanol + carbon dioxide

Question 9

Name an advantage and disadvantage of using fermentation to produce ethanol

Answer 9

Advantage - renewable, uses a low temperature and cheap equipment
Disadvantage - produces impure ethanol which needs to be distilled. Fermentation takes time.

Question 10

What is a monomer

Answer 10

A single molecule which makes a polymer

Question 11

What is a polymer

Answer 11

A long chain made from the same repeating molecule (monomer)

Question 12

Name the polymer made from the polymerisation of ethene

Answer 12

Poly(ethene)

Question 13

Name the monomer needed to produce the polymer, polychloroethene

Answer 13

Chloroethene

Question 14

Describe the steps to extract oils from plants

Answer 14

• Plant material is crushed
• Oil is separated using a centrifuge
• Oil is refined using distillation

Question 15

Name two uses of vegetable oils

Answer 15

Cooking

Use for biodiesel

Question 16

Why are oils used for cooking

Answer 16

High boiling point

Adds flavour

Question 17

Describe the process of hydrogenation

Answer 17

• Unsaturated vegetable oil is reacted with hydrogen
• with a nickel catalyst
• at about 60oC

Question 18

Name a health effect of eating saturated fats, such as animal fats

Answer 18

Raises cholesterol levels in blood

Can cause heart disease

Question 19

What is an emulsion?

Answer 19

Droplets of a liquid suspended in another liquid

Question 20

Describe how an emulsion works

Answer 20

Emulsfier has a hydrophilic head and a hydrophobic tail
The hydrophilic end attracts water
The hydrophobic end attracts oil
This stops the mixture separating