6 - The Production And Uses Of Fuels And Plastics

Question 1

What is crude oil?

Answer 1

A hydrocarbon

Question 2

What happens to crude oil in an oil refinery?

Answer 2

• compounds in the oil are separated into smaller groups called fractions using fractional distillation
• each fraction contains a mix of hydrocarbons with a similar number of carbon atoms

Question 3

What is fractional distillation?

Answer 3

• a process used to separate a mixture of liquids that have different boiling points
• liquids with a higher boiling point remain as liquid. The vapour can then be separated from the liquid (used to separate crude oil into fractions)
• they have similar boiling points because the molecules are similar sozes

Question 4

How is crude oil separated into fractions?

Answer 4

• oil is heated to 370C and pumped into the bottom of a fractionating column where it vapourizes
• the column is hot at the bottom and cool at the top. As the vapourized oil roses, it cools and condenses
• heavy fractions have high boiling points and condense near the bottom of the column
• lighter fractions have lower boiling points and condense further up the column

Question 5

How do fractions differ? (4)

Answer 5

• boiling point
• the number of carbon and hydrogen atoms they contain
• viscosity (thickness)
• easy of ignition

Question 6

What is catalyst cracking?

Answer 6

The breaking down of long-chain hydrocarbon molecules into smaller molecules using a catalyst

Question 7

What are alkenes?

Answer 7

Reactive molecules that are used to make plastics and other chemicals

Question 8

What is a monomer?

Answer 8

-small molecule that contains a Carbon double bond

Question 9

How are monomers made?

Answer 9

From cracking hydrocarbons from crude oil

Question 10

Why are monomers reactive?

Answer 10

Because they have a double bond

Question 11

What is polymerisation?

Answer 11

The joining of small molecules using heat and a catalyst to make larger molecules

Question 12

Properties and uses of PVC

Answer 12

Properties:
-strong, resistant to corrosion, good insulator

Uses:
-window frames, electrical cable coverings

Question 13

Properties and uses of polyethene

Answer 13

Prop:
-strong, easy to mould

Uses:
-plastic bags, buckets, yoghurts

Question 14

Properties and uses of PTFE

Answer 14

Prop:
-non-stick, hard, waxy

Uses:
-baking sheets, coating for pans, linings for cake tind

Question 15

Properties and uses of polystyrene

Answer 15

Prop:
-easily moulded, can be expanded into foam
Uses:
-hot food containers/cups, insulating materials, packaging

Question 16

What problems do non-biodegradable plastics cause?

Answer 16

• difficult to get rid off
• when burnt, poisonous gases can be released
• don’t rot

Question 17

How is crude oil formed?

Answer 17

• tiny animals in the sea died and sank to the ocean floor. Layers built up that got buried and compressed
• over millions of years the animals turned into crude oil. They did not decay due to the conditions of no oxygen and intense pressure