Crude Oil

Question 1

What is crude oil?

Answer 1

Crude oil is a mixture of different hydrocarbons.

Question 2

True or False?

Each fraction in crude oil consists of groups of hydrocarbons with similar chain lengths.

Answer 2

True.

Each fraction in crude oil consists of groups of hydrocarbons with similar chain lengths.

Question 3

Define fractional distillation.

Answer 3

Fractional distillation is the process of separating the different fractions of crude oil based on their boiling points.

Question 4

True or False?

The size and length of each hydrocarbon molecule determines which fraction it will be separated into.

Answer 4

True.

The size and length of each hydrocarbon molecule determines which fraction it will be separated into.

Question 5

True or False?

As you move up a fractionating column, the temperature increases.

Answer 5

False.

As you move up a fractionating column, the temperature decreases.

Question 6

What happens to the viscosity of a liquid as the number of carbon atoms increases?

Answer 6

As the number of carbon atoms increases, the viscosity of the liquid increases.

Question 7

What happens to the volatility of a hydrocarbon liquid as the molecular size increases?

Answer 7

As the molecular size increases, the volatility of a hydrocarbon liquid decreases.

Question 8

Define the term viscosity.

Answer 8

Viscosity is the ease of flow of a liquid.

Question 9

What is the use of liquefied petroleum gas?

Answer 9

Liquefied petroleum gas is used for domestic heating & cooking.

Question 10

True or False?

Kerosene is used as jet fuel.

Answer 10

True.

Kerosene is used as jet fuel (paraffin).

Question 11

What is diesel used for?

Answer 11

Diesel is used in diesel engines (gas oil).

Question 12

Give a use of heavy fuel oil.

Answer 12

Heavy fuel oil is used for ships & power stations.

Question 13

Which fraction is used to surface roads?

Answer 13

The fraction used for surfacing roads is bitumen.

Question 14

What are the products of complete combustion of hydrocarbons?

Answer 14

The products of complete combustion of hydrocarbons are carbon dioxide and water.

Question 15

Define incomplete combustion.

Answer 15

Incomplete combustion occurs when there is insufficient oxygen to burn the fuel completely.

Question 16

What are the products of incomplete combustion?

Answer 16

The products of incomplete combustion are carbon monoxide, carbon (soot) and water.

Question 17

True or False?

Carbon dioxide is not a pollutant causing global warming and climate change.

Answer 17

False.

Carbon dioxide is a pollutant causing global warming and climate change.

Question 18

How does carbon monoxide cause harm?

Answer 18

Carbon monoxide binds well to haemoglobin, preventing it from binding to oxygen and transporting oxygen to organs.

Question 19

Name one place that incomplete combustion can occur.

Answer 19

Incomplete combustion occurs in some appliances such as:

Boilers

Stoves

Internal combustion engines

Question 20

What is the symbol equation for the complete combustion of propane?

Answer 20

The symbol equation for the complete combustion of propane is:

C3H8 + 5O2 → 3CO2 + 4H2O

Question 21

Balance the following symbol equation for the incomplete combustion of ethane.

C2H6 + O2 → CO + H2O

Answer 21

The balanced symbol equation for the incomplete combustion of ethane is:

C2H6 + 2.5O2 → 2CO + 3H2O

Question 22

Name three gases that the burning of fossil fuels releases.

Answer 22

Three gases that the burning of fossil fuels releases:

Carbon dioxide

Carbon monoxide

Oxides of nitrogen

Oxides of sulfur

Question 23

Where are nitrogen oxides formed?

Answer 23

Nitrogen oxides are formed in the high pressure and temperature conditions of internal combustion engines and blast furnaces.

Question 24

State the equation for sulfur being oxidised to sulfur dioxide.

Answer 24

The equation for the oxidation of sulfur is:

S (s) + O2 (g) → SO2 (g)

Question 25

How is acid rain formed from nitrogen and sulfur oxides?

Answer 25

Acid rain is formed by nitrogen and sulfur oxides dissolve in rainwater to form nitric acid and sulfuric acid, respectively.

Question 26

What are two harmful effects of sulfur dioxide?

Answer 26

Harmful effects of sulfur dioxide include: Acid rain Corrosion of buildings and structures Damage to aquatic organisms Damage to plant life Respiratory problems

Question 27

How do catalytic converters work?

Answer 27

Catalytic converters contain transition metal catalysts that convert pollutant gases to less harmful substances through redox reactions.

Question 28

Name the two gases that contribute to acid rain.

Answer 28

Two gases that contribute to acid rain are nitrogen dioxide and sulfur dioxide.

Question 28

State the equation for nitrogen oxides (NO and NO2) being reduced to nitrogen and oxygen.

Answer 28

The equations for the reduction of nitrogen oxides are: 2NO → N2 + O2 2NO2 → N2 + 2O2

Question 29

How is sulfur dioxide produced from the burning of fossil fuels?

Answer 29

During combustion, the sulfur impurities in the fossil fuels get oxidised / react with oxygen to form sulfur dioxide.

Question 30

Write an equation to show the formation of acid rain, H2SO4 (aq), from sulfur dioxide, water and oxygen.

Answer 30

The equation to show the formation of acid rain, H2SO4 (aq), from sulfur dioxide, water and oxygen is: 2SO2 (g) + O2 (g) + 2H2O (l) → 2H2SO4 (aq)

Question 31

What is the purpose of cracking?

Answer 31

The purpose of cracking is to convert surplus unwanted fractions of crude oil, such as kerosene and diesel oil, into more useful fractions like petrol (gasoline), alkenes, and hydrogen.

Question 32

True or False? The demand for certain fractions outstrips the supply, which is why cracking is necessary.What are the two methods used for cracking alkanes?

Answer 32

True. The demand for certain fractions outstrips the supply, which is why cracking is necessary to convert surplus unwanted fractions into more useful ones.

Question 32

True or False? Cracking is an exothermic reaction

Answer 32

False. Cracking is an endothermic reaction.

Question 33

What is the equation for the cracking of decane to produce octane and ethene?

Answer 33

The equation for the cracking of decane to produce octane and ethene is: C10H22 → C8H18 + C2H4

Question 34

True or False? Alkanes are saturated compounds, and alkenes are unsaturated compounds.

Answer 34

True. Alkanes are saturated compounds, and alkenes are unsaturated compounds.

Question 35

Name the catalyst used in catalytic cracking.

Answer 35

The catalyst used in catalytic cracking is: Alumina / aluminium oxide / Al2O3 OR Silica / silicon dioxide / SiO2

Question 36

True or False? Cracking is a type of substitution reaction.

Answer 36

False: Cracking is a type of thermal decomposition reaction.

Question 37

True or False? Long chain fractions are in high supply but in low demand.

Answer 37

True. Long chain fractions are in high supply but in low demand. This explains why they are cracked into more useful, shorter chain alkanes and alkenes.

Question 38

Name a longer chain fraction of crude oil.

Answer 38

Examples of longer chain fractions of crude oil are: Fuel oil Bitumen