Fractional distillation & petrochemicals

Crude oil is a source of hydrocarbons.

Which chemical is a hydrocarbon?

Tick (✓) one box.

Complete the sentences about crude oil.

Use words from the list.

cracking filtration fractional distillation neutralisation reduction

The hydrocarbons in crude oil are separated by........

Some of these hydrocarbons are made more useful by........

The table shows the description of three resources A, B and C.

Which resource is crude oil?

Explain your choice using information from the table.

Crude oil is resource........

Reason........

Scientists think that increased levels of carbon dioxide are causing global warming.

Which statements about the potential effects of global warming are true and which are false ?

Tick (✓) one box in each row.

The diagram shows information about a fraction produced in the fractional distillation of crude oil.

What is a correct statement about the fraction produced at the bottom of the fractional distillation column?

A It has a high boiling point.

B It is a gas.

C Its intermolecular forces are weak.

D Its molecules are small.

Crude oil is a source of useful chemicals called hydrocarbons.

Complete the sentence about crude oil.

Crude oil is a compound / feedstock / renewable resource used by the petrochemical industry.

The diagram shows the fractionating column used in the fractional distillation of crude oil.

Which state symbol describes the crude oil as it enters the fractionating column?

Tick (✓) one box.

Write an X on the fractionating column where it is coolest.

The table shows the boiling point of four hydrocarbons.

Which of the hydrocarbons P, Q, R or S is produced nearest to the top of the fractionating column?

Which of the hydrocarbons P, Q, R or S has the largest molecules?

Large hydrocarbons can be made more useful by cracking.

The equation shows the cracking of hydrocarbon X.

What is the formula of hydrocarbon X ?

Which homologous series of hydrocarbons does C₆H₁₄ belong to?

The hydrocarbon C₂H₄ belongs to a different homologous series.

Suggest the general formula of the homologous series that contains C₂H₄.

Tick one (✓) box.

Crude oil is a mixture of useful hydrocarbons which are separated into fractions.

Which statement describes why crude oil is called a feedstock for the petrochemical industry?

Tick one (✓) box.

Table 13.1 shows some information about the fractions in crude oil.

Table 13.1

Calculate the percentage of fraction W found in crude oil.

Write your answer in Table 13.1.

The boiling point of a fraction depends on the number of carbon atoms in the molecules.

Complete Table 13.2 by writing in the letters of three fractions shown in Table 13.1.

Table 13.2

Write the letter of the fraction shown in Table 13.1 which has the strongest intermolecular forces.

Many of the hydrocarbons in crude oil are alkanes.

Write the general formula for an alkane.

Write the formula for an alkane with 14 carbon atoms.

Fig. 12.1 shows the separation of the chemicals found in crude oil.

Fig. 12.1

Gases

What is the name of the process shown in Fig. 12.1 ?

Crude oil is heated and vaporised as it enters the column.

Describe what happens to the vapours as they rise up the column.

Which of the chemicals separated from crude oil has the smallest molecules?

Tick (✓) one box.

Fig. 12.2 shows the structure of a molecule found in crude oil.

Fig. 12.2

Which words describe the molecule?

Tick (✓) two boxes.

There are other molecules similar to Fig. 12.2 but with different numbers of carbon atoms.

Fig. 12.3 shows how the boiling point of these molecules changes with the number of carbon atoms in the molecule.

Fig. 12.3

Number of carbon atoms in the molecule

Use the graph to estimate the boiling point of the molecule shown in Fig. 12.2.

160 litres of crude oil contains 75 litres of petrol.

Calculate the percentage of petrol in the crude oil.

Give your answer to 2 significant figures.

The diagram shows the fractional distillation of crude oil.

Gases

Which row in the table describes the Gases fraction?

The diagram shows how crude oil is separated into its fractions in a fractionating column.

Gases

What is the physical state of the crude oil as it enters the fractionating column?

A Aqueous

B Gas

C Liquid

D Solid

The processing of crude oil by the petrochemical industry can be shown by different experiments.

The diagram shows how crude oil can be separated into its fractions.

The crude oil is heated. Different fractions are collected at different temperatures.

What is the name of this separation technique?

Explain how a fraction is separated and collected in the experiment.

A fraction with a boiling point of about 10 °C is not collected in the experiment.

How could the experiment be improved so this fraction is collected?

The table shows the temperatures at which four different fractions are collected.

Which statements about the fractions are true, and which are false ?

Tick (✓) one box in each row.

Crude oil is a mixture of different chemicals called fractions.

What is the name of the process used to separate crude oil into fractions?

Table 13.1 shows the stages in the separation of crude oil into fractions.

The stages are not in the correct order.

Write W, X, Y and Z in the boxes to show the correct order of the stages.

Table 13.2 shows information about the different gases in the LPG (liquefied petroleum gas) fraction separated from crude oil.

Write the name of the homologous series of the gases in the LPG fraction.

Use the data in Table 13.2 to estimate the boiling point of butane.

The equation shows the reaction for methane burning in a limited amount of oxygen.

Write down the name of the hazardous gas formed in this reaction.

State why the gas identified in (d)(i) is hazardous to humans.

Crude oil is a mixture of alkanes which can be separated into different fractions.

The different fractions have a range of different boiling points.

The diagram shows the process of fractional distillation.

Explain how fractional distillation separates the crude oil into fractions.

Icosane, C₂₀H₄₂, is an alkane found in one of the fractions.

It has a boiling point of 343 °C.

Which fraction, A, B, C, D, E or F, contains icosane?

Icosane is converted into more useful products by cracking.

State the two conditions used for cracking.

Many different products can form when cracking icosane.

In one reaction, a molecule of icosane (C₂₀H₄₂) forms a molecule of hydrogen, H₂, and one other product.

Write the balanced symbol equation for this reaction.

* Fraction A contains the alkanes methane, ethane, propane and butane.

Table 14.1 shows some information about these four alkanes.

Describe and explain the similarities and differences in the boiling point of these four alkanes.

Use information in Table 14.1 and your knowledge of structure and bonding in your answer.

Crude oil can be separated into useful substances called fractions.

Write down the name of the process that separates crude oil into fractions.

Name the fractions A and B.

A........

B........

Here are the boiling ranges for petrol and diesel.

How do the sizes of molecules in petrol and diesel differ?

Explain why the boiling range for petrol is different from the boiling range for diesel.

Not enough petrol is made from crude oil to meet world demand.

Oil refineries make more petrol using a process called cracking.

Describe how cracking makes more petrol from other hydrocarbons.

Include the conditions needed.

Which statement about the fractional distillation of crude oil is correct?

A Diesel leaves the fractionating column at the bottom.

B Petrol leaves the fractionating column at the top.

C The fractionating column is hottest at the top.

D The hydrocarbons in crude oil can be separated because they have different boiling temperatures.