Hydrocarbons

Question 1

What is crude oil?

Answer 1

It is a mixture of lots of different hydrocarbon molecules

Question 2

How is crude oil used in fractional distillation?

Answer 2

Crude oil is vapourised and the vapour is then slowly cooled. As the temperature drops, first the larger and then the smaller liquids turn to liquids and can be collected. This separates them into FRACTIONS

Question 3

What are some products from fractional distillation?

Answer 3

• gases for heating and cooking
• petrol for cars
• kerosene for aircraft fuel
• diesel oil for some cars and trains
• fuel oil for ships and power station
• bitumen for tarmac and roofing

Question 4

Define HOMOLOGOUS SERIES

Answer 4

A family of similar compounds

Question 5

What is the relationship between the size of a molecule and the strength of intermolecular forces?

Answer 5

As the molecules get longer, the intermolecular forces get stronger. The stronger the force, the more kinetic energy (higher temperature) needed to boil the fraction

Question 6

What happens when hydrocarbons burn and there is not enough oxygen?

Answer 6

INCOMPLETE COMBUSTION - they produce carbon monoxide

Question 7

What is an indicator of incomplete combustion?

Answer 7

a yellow sooty flame

Question 8

What does carbon monoxide do to cells in the body?

Answer 8

Carbon monoxide combines permanently with haemoglobin in red blood cells. This prevents them from carrying oxygen