Crude oil and fuels

Question 1

What are the alkanes?

Answer 1

The alkanes are a family of hydrocarbons that have adjacent carbon atoms joined by a single covalent bond.

Question 2

What state is Methane, Ethane, Propane and Butane in at room temperature?

Answer 2

Colourless gases

Question 3

All the alkanes are ________ in water.

Answer 3

Insoluble

Question 4

What is a homologous series?

Answer 4

A family of similar compounds.

Question 5

What can be created when alkanes are burned without enough oxygen? (incomplete combustion)

Answer 5

Carbon monoxide

Question 6

What does the combustion of hydrocarbons involve when there is a good oxygen supply?

Answer 6

• The release

- The oxidation of carbon and hydrogen to create carbon dioxide and water.

Question 7

Why don’t heavy fractions of crude oil make good fuels?

Answer 7

• Have low volatility
• Don’t ignite easily
• Have high boiling points

Question 8

What are hydrocarbons?

Answer 8

Organic compounds made of carbon and hydrogen.

Question 9

What are the uses of alkenes?

Answer 9

• Being combined to make polymers

- Starting materials for chemicals like ethanol

Question 10

What is fractional distillation?

Answer 10

The process of separating crude oil into groups of hydrocarbons with similar numbers of carbon atoms. We call these groups of hydrocarbons “fractions”.

Question 11

Different-sized hydrocarbons have different boiling points. Fractional distillation separates hydrocarbons using their different boiling points. What are the steps to the process of fractional distillation?

Answer 11

1. EVAPORATION
   - We evaporate the crude oil by heating it.
   - Crude oil vapour is put into a fractionating column at the bottom and rises upwards.
2. CONDENSATION
   - The temperature is highest at the bottom of the column. Long-chain hydrocarbons condense at the bottom and are collected as liquids.
   - Short-chain hydrocarbons have lower boiling points. They pass up the column and condense at lower temperatures nearer the top

3.COLLECTION
The fuels are collected. They are then processed to create end products:
- Fuels (e.g. petrol, diesel) are a common end product.
- The petrochemical industry can use some fractions as feedstock (material used in an industrial process) to make products such as solvents, detergents, lubricants etc.