4b

Question 1

Crude oil

Answer 1

Mixture of hydrocarbons

Question 2

Crude oil separation

Answer 2

1. It is heated, vaporised in a fractional distillation tower (hotter at the bottom, cooler at the top)
2. Gases travel until the temperature is lower than the boiling point, then they turn into a liquid

(except natural gases, which stay as gases and bitumen that comes off at the bottom and never turns into a gas)

The boiling point and viscosity decrease as you go down
Flammability increases as you go up

Question 3

Crude oil fractions

Answer 3

• Natural gases
• Petrol / Gasoline
• Kerosine
• Diesel
• Fuel oil
• Bitumen

Question 4

Natural gases

Answer 4

Home heating

Question 5

Petrol / Gasoline

Answer 5

Car fuel

Question 6

Kerosene

Answer 6

Plane fuel

Question 7

Diesel

Answer 7

Bus/Lorrie fuel

Question 8

Fuel oil

Answer 8

Boat/Power station fuel

Question 9

Bitumen

Answer 9

Roads

Question 10

Fuel

Answer 10

A substance that releases energy when burnt

Question 11

Nitrogen oxide formation

Answer 11

• In car engines
• If the temperature is high enough, Nitrogen in the air reacts with oxygen to form nitrogen oxygen

Question 12

Sulfur dioxide formation

Answer 12

• Fuels can contain impurities such as sulfur
• When these impure fuels are burnt, sulfur dioxide is produced

Question 13

Cracking

Answer 13

Spliting larger alkanes(less value) into smaller alkanes(more value) and alkenes (and/or hydrogen)

Requires: Heat(600-700 ºC), Catalyst(silica or alumina)

Longer alkane –> Shorter Alkane + Alkene

Question 14

Why is cracking useful

Answer 14

• Produces smaller, more valuable in demand hydrocarbons.
• Less demand for longer alkanes
• That are used for fuels or polymers