Fractional distillation and petrochemicals

Alkanes are used as fuels.

Butane is an alkane.

Figure 4 shows butane being used to heat a copper kettle.

The use of butane as a fuel involves a combustion reaction.

What gas in the air does butane react with during combustion?

Why is copper a suitable material for a kettle?

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Copper can be shaped.

Copper has a low melting point.

Copper reacts with water.

Figure 5 represents a butane molecule.

What is the type of bonding in a butane molecule?

Use Figure 5.

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Covalent

Ionic

Metallic

What type of structure does butane have?

Use Figure 5.

Tick () one box.

Giant structure

Polymer

Small molecule

Table 2 shows the melting points and boiling points of three alkanes.

Which alkane is a liquid at − 185 °C?

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Ethane

Propane

Butane

Hydrocarbons in crude oil are separated into fractions using fractional distillation.

Figure 8 shows a fractional distillation column.

What is the name of the process that produces the diesel oil fraction at Z on Figure 8 ?

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Condensing

Freezing

Melting

Different hydrocarbons have different-sized molecules.

Crude oil contains different percentages of each fraction.

Table 4 shows information about petrol and heavy fuel oil.

The supply of petrol is not enough to meet the demand for petrol.

The additional petrol needed can be produced by cracking other fractions.

Cracking breaks down larger molecules into smaller molecules.

Give two reasons why heavy fuel oil is a suitable fraction to be cracked to produce petrol.

The products of cracking include another type of hydrocarbon called alkenes.

Small alkene molecules can join together to produce long-chain molecules.

What type of reaction produces long-chain molecules?

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Decomposition

Oxidation

Polymerisation

Plastics are produced from alkenes.

Drinks can be sold in plastic bottles or glass bottles.

Table 5 shows information about some plastic bottles and some glass bottles.

Explain why less energy is used to transport the same volume of liquid in plastic bottles than in glass bottles.

Some plastic bottles are disposed of as waste in landfill sites.

Suggest two ways that people can reduce the environmental impact of plastic bottles.

Crude oil is a mixture of compounds.

Most of the compounds are hydrocarbons called alkanes.

Propane is an alkane.

The formula of propane is C₃H₈

Complete the general formula for alkanes.

C_nH _________

Table 4 shows information about some alkanes.

Predict the value of X in Table 4.

Explain the trend in boiling points shown in Table 4.

Propane is used as a fuel.

Write a balanced equation for the complete combustion of propane (C₃H₈).

Hydrocarbons in crude oil are separated into fractions using fractional distillation.

Figure 16 shows a fractional distillation column.

Explain how crude oil is separated into fractions by fractional distillation.

How do the viscosity and boiling point of heavy fuel oil compare with the other fractions in Figure 16 ?

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Heavy fuel oil is the least viscous and has the highest boiling point.

Heavy fuel oil is the least viscous and has the lowest boiling point.

Heavy fuel oil is the most viscous and has the highest boiling point.

Heavy fuel oil is the most viscous and has the lowest boiling point.

This question is about hydrocarbons.

Name the two elements in a hydrocarbon.

Which two of the following substances are hydrocarbons?

Tick (✓) two boxes.

Ammonia

Ethene

Graphite

Methane

Steam

C₆H₁₄ is a hydrocarbon.

C₆H₁₄ can be broken down into smaller molecules.

Complete the equation for the breakdown of C₆H₁₄ into smaller molecules.

What is the name of the process t hat breaks d own C₆H₁₄ into smaller molecules?

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Cracking

Distillation

Neutralisation

How does the boiling point of C₆H₁₄ compare with the boiling point of C₄H₁₀?

Give one reason for your answer.

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C₆H₁₄ has a lower boiling point.

C₆H₁₄ and C₄H₁₀ have the same boiling point.

C₆H₁₄ has a higher boiling point.

The complete combustion of C₆H₁₄ produces water and one other product.

Name the other product of the complete combustion of C₆H₁₄

Do not refer to water in your answer.

The formula of water is H₂O

Calculate the relative formula mass (M_r) of water.

Relative atomic masses (A_r): H = 1 O = 16

This question is about hydrocarbon fuels.

The complete combustion of a hydrocarbon fuel produces carbon dioxide and one other product.

Name the other product of the complete combustion of a hydrocarbon fuel.

Do not refer to carbon dioxide.

Describe the test for carbon dioxide.

Give the result if carbon dioxide is present.

The combustion of hydrocarbon fuels releases energy.

A student investigated the energy released by three different fuels A, B and C.

Figure 11 shows the apparatus.

This is part of the method used.

1. Put fuel A in the burner.

2. Pour 100 cm³ of water into the conical flask.

3. Record the temperature of the water.

4. Light the fuel and heat the water for 5 minutes.

5. Record the final temperature of the water.

6. Repeat steps 1 to 5 using fuel B and then using fuel C.

The student also determined the mass of fuel burnt.

Describe how the student could determine the mass of fuel burnt.

Give one control variable in the investigation.

Table 5 shows the results.

Explain how Table 5 shows that fuel C released the most energy per gram of fuel.

The student repeated the investigation with screens around the apparatus.

Figure 12 shows the apparatus with screens.

Give one reason why putting screens around the apparatus could improve the accuracy of the investigation.

How would stirring the water improve the accuracy of the investigation?

This question is about hydrocarbon fuels.

The complete combustion of a hydrocarbon fuel produces carbon dioxide and one other product.

Name the other product of the complete combustion of a hydrocarbon fuel.

Do not refer to carbon dioxide.

Describe the test for carbon dioxide.

Give the result if carbon dioxide is present.

The combustion of hydrocarbon fuels releases energy.

A student investigated the energy released by three different fuels A, B and C.

Figure 1 shows the apparatus.

This is part of the method used.

1. Put fuel A in the burner.

2. Pour 100 cm³ of water into the conical flask.

3. Record the temperature of the water.

4. Light the fuel and heat the water for 5 minutes.

5. Record the final temperature of the water.

6. Repeat steps 1 to 5 using fuel B and then using fuel C.

The student also determined the mass of fuel burnt.

Describe how the student could determine the mass of fuel burnt.

Give one control variable in the investigation.

Table 1 shows the results.

Explain how Table 1 shows that fuel C released the most energy per gram of fuel.

The student repeated the investigation with screens around the apparatus.

Figure 2 shows the apparatus with screens.

Give one reason why putting screens around the apparatus could improve the accuracy of the investigation.

How would stirring the water improve the accuracy of the investigation?

This question is about hydrocarbons.

What is the maximum number of bonds that one carbon atom can form?

Tick (✓) one box.

2 3 4 6

Most of the compounds in crude oil are hydrocarbons.

Crude oil is the remains of an ancient biomass.

What did the ancient biomass mainly consist of?

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Methane

Plankton

Rocks

Fractional distillation is used to separate the hydrocarbons in crude oil into fractions.

Which property of hydrocarbons is used to separate them?

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Boiling point

Flammability

Viscosity

Name one fuel produced from the fractional distillation of crude oil.

What are the two products of the complete combustion of a hydrocarbon?

Tick (✓) two boxes.

Ammonia

Carbon dioxide

Nitrogen

Oxygen

Water

How does the size of the molecules affect the viscosity of hydrocarbons?

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Smaller hydrocarbon molecules have greater viscosity.

The size of the hydrocarbon molecules does not affect the viscosity.

Larger hydrocarbon molecules have greater viscosity.

Crude oil is a mixture containing hydrocarbons.

Alkanes are hydrocarbons.

Figure 10 represents an alkane.

X and Y represent atoms of different elements in an alkane.

Label element X and element Y on Figure 10.

What is represented by Z on Figure 10 ?

Crude oil is separated into fractions in a fractionating column.

Figure 11 shows a fractionating column.

Table 2 gives some properties of different fractions separated from crude oil.

Label Figure 11 to show where diesel, heavy fuel oil and kerosene fractions are collected.

Use Table 2.

Complete the sentences.

Choose answers from the box.

Which statement about the flammability of petrol and diesel is correct?

Use Table 2.

Tick (✓) one box.

Table 2 is repeated here.

Octane is a hydrocarbon obtained from crude oil.

Octane has 8 carbon atoms.

Which fraction in Table 2 contains octane?

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Name the two substances produced from the complete combustion of octane.

This question is about the hydrocarbons obtained from crude oil.

Octane is a hydrocarbon.

How does the formula of octane show that octane is an alkane?

The fractions in crude oil are separated by fractional distillation.

Figure 6 shows a fractionating column.

Table 3 gives some properties of different fractions separated from crude oil.

Which fraction in Table 3 is the most viscous?

Give one reason for your answer.

Tick (✓) one box.

Describe how the fraction containing octane is separated from crude oil.

Use data from Table 3 in your answer.

This question is about hydrocarbons.

Figure 6 represents hydrocarbon A.

Complete the chemical formula of hydrocarbon A.

C₅

What do the links between the atoms in Figure 6 represent?

Hydrocarbon A is a fuel. Hydrocarbon A is completely combusted in air.

Which two substances are produced?

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Some students investigated how changing the temperature of a hydrocarbon affects the viscosity of the hydrocarbon.

Figure 7 shows the apparatus used.

The students recorded the time it took for 25 cm³ of the hydrocarbon to flow through the hole in the viscometer.

Table 3 shows a student’s results at 60 °C

Calculate the mean value X.

Another student investigated a different hydrocarbon.

Table 4 shows the results.

Complete Figure 8.

You should:

• plot the data from Table 4

• draw a line of best fit.

Describe the pattern shown on Figure 8.

The viscosity of a substance is linked to how fast the substance flows.

The lower the viscosity, the faster the substance flows.

Complete the sentence.

Choose the answer from the box.

As the temperature increases, the viscosity of

the hydrocarbon.

This question is about hydrocarbons.

When a hydrocarbon C₁₀H₂₂ is cracked, two substances are produced.

Complete the equation for the reaction.

Explain why the hydrocarbon C₇H₁₆ has a lower boiling point than C₁₀H₂₂

Ethanol is produced by reacting ethene with steam.

The equation for the reaction is:

Figure 4 shows the percentage yield of ethanol using different reaction conditions.

Explain why changing the pressure affects the percentage yield of ethanol.

The forward reaction is exothermic.

How does Figure 4 provide evidence for this?

Figure 5 shows part of a reaction profile diagram.

A catalyst is used in the reaction to produce ethanol.

Complete Figure 5 to show how the catalyst increases the rate of this reaction.

You should label the reaction profile diagram.

Suggest why the catalyst does not affect the yield of ethanol at equilibrium.