Alkanes And Fuel

1. Fractional distillation is used to separate crude oil into various fractions. Which property of the different fractions enable them to be separated?

They have different densitites

They have different boiling points.

They have different solubilities in crude oil.

They have different viscosities.

2. Methane is used as a fuel. What property is essential for this use?

It burns exothermically

It is odourless.

It is a gas.

It has a low boiling point.

3. Which statement about 'fossil fuel' is not true?

They all contain carbon.

They are renewable.

They produce pollutants when burnt.

They may cause acid rain.

4. Which of the following is not made from crude oil?

Aircraft fuel

Diesel oil

Furniture polish

Margarine

5. What is the main constituent of natural gas?

Ethene

Hydrogen

Propane

Methane

6. Which fraction contains the largest molecules?

Kerosene

Petrol

Diesel

Bitumen

7. Which of the following fraction is used as chemical feedstock?

Lubricating oil

Bitumen

Naphtha

Kerosene

8. Study the reaction scheme below.

What is process I and II?

I is substitution; II is addition

I is cracking; II is fractional distillation

I is fractional distillation; II is cracking.

I is decomposition; II is substitution

9. During cracking, a hexane molecule was being split into smaller molecules.

Hexane ----> butane + substance X

What is substance X?

Ethane

Ethene

Ethanol

Ether

10. Why are large alkane molecules cracked to form smaller molecules?

Alkanes with large molecules are not useful.

Small alkane molecules can be polymerized.

Crude oil does not contain small alkane molecules.

To meet the demand for small alkane molecules.