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Organic chemistry Low demand 1 – Questions

Q1.Crude oil and natural gas are natural resources in many countries.

The table shows percentages of hydrocarbons in natural gas from three different countries.

HydrocarbonPercentage (%) of hydrocarbon in natural

gas

Country X Country Y Country Z

Methane 78.03 88.10 94.36

Ethane 9.70 5.30 2.37

Propane 4.82 2.16 0.15

Butane 1.33 0.72 0.02

Pentane 0.30 0.18 0.00

(a) Calculate the mean percentage of propane from countries X, Y and Z.

Give your answer to 2 decimal places.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

Mean percentage of propane = ____________________ %(2)

(b) Suggest why natural gas from different countries has different percentages of hydrocarbons.

___________________________________________________________________

___________________________________________________________________(1)

(c) Complete the sentence.

Choose the answer from the box.

an atom an electron an ion a molecule

The formula CH4 represents ____________________ of methane.(1)

(d) Complete the sentence.

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The hydrocarbons in the table belong to the homologous series of

____________________ .(1)

Figure 1 shows how properties vary with the increasing size of molecule in this homologous series.

Figure 1

(e) Which graph shows how boiling points vary?

Tick one box.

A B C D

(1)

(f) Which graph shows how viscosity varies?

Tick one box.

A B C D

(1)

(g) Crude oil is fractionally distilled.

Fractions with larger molecules are cracked.

Describe two differences between fractional distillation and cracking.

1. _________________________________________________________________

___________________________________________________________________

2. _________________________________________________________________

___________________________________________________________________(2)

(h) Ethene is a product of crude oil.

Complete the sentence.

Ethene polymerises to produce ____________________ .

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(1)

(i) The production of plastic bags uses limited resources.

Figure 2 shows two ways (A and B) of saving limited resources.

Figure 2

Name A and B.

Choose the answers from the box.

recycle reduce release reuse reverse

A ____________________

B ____________________(2)

(Total 12 marks)

Q2.The apparatus in the figure below is used to separate a mixture of liquids in a fuel.

(a) What is apparatus W on above the figure above?

Tick one box.

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Beaker

Boiling Tube

Flask

Jug

(1)

(b) What is the name of this method of separation?

Tick one box.

Crystallisation

Electrolysis

Filtration

Distillation

(1)

(c) Name the changes of state taking place at A and B in the figure above.

Use words from the box.

boiling condensing freezing melting

Change of state at A: _________________________________________________

Change of state at B: _________________________________________________(2)

(d) Table 1 shows the boiling points of the hydrocarbons in the fuel.

Table 1

Hydrocarbon Boiling pointin °C

Pentane 36

Hexane 69

Heptane 98

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Octane 125

Which hydrocarbon will be the last to collect in the beaker?

Tick one box.

Pentane

Hexane

Heptane

Octane

(1)

(e) The fuel is a mixture of liquids that has been designed as a useful product.

What name is given to this type of mixture?

Tick one box.

Catalyst

Formulation

Polymer

Solvent

(1)

(f) Describe how this fuel is different from crude oil.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________(2)

(g) A student measured the melting point of a solid hydrocarbon four times.

The student’s results are in Table 2.

Table 2

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Trial 1 Trial 2 Trial 3 Trial 4

Melting point in °C 35 48 37 37

Calculate the mean melting point of the hydrocarbon, leaving out any anomalous result.

Give your answer to two significant figures.

___________________________________________________________________

___________________________________________________________________

Mean melting point = __________________ °C(2)

(Total 10 marks)

Q3.A student investigated the substances produced when fuels burn.

The figure below shows the apparatus the student used.

(a) The complete combustion of a hydrocarbon produces carbon dioxide and one other substance.

Look at the figure above. What would the student see in tube A?

___________________________________________________________________

___________________________________________________________________(1)

(b) When the student burned the fuel she saw soot in the funnel.

Explain why soot forms.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

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___________________________________________________________________(2)

(c) The student burned another fuel which contained impurities.

The substance in tube B is water containing universal indicator.

The indicator turned red.

Which gas made the indicator turn red?

Tick one box.

Ammonia

Carbon monoxide

Nitrogen

Sulfur dioxide

(1)(Total 4 marks)

Q4.There are several different forms of carbon and many different carbon compounds.

(a) Figure 1 shows a 3D model of a molecule of methane (CH4).

Figure 1

Draw the 2D structure of a methane molecule.(1)

(b) Different forms of carbon have different bonding and structure.

Draw one line from the form of carbon to the bonding and structure.

Form of carbon Bonding and structure

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(3)

(c) Crude oil is a mixture of many different carbon compounds.

Crude oil can be separated into useful fractions by fractional distillation.

Figure 2 shows a column used to separate crude oil.

Figure 2

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Complete the sentences.

Use words from the box.

condense evaporate freeze

Crude oil is heated so that most of the compounds ____________________

At different temperatures the compounds cool and ____________________(2)

(d) Which fraction is the most viscous?

Tick one box.

Engine oil

Diesel oil

Kerosene

Petrol

(1)

(e) Which fraction is the most flammable?

Tick one box.

Diesel oil

Kerosene

Petrol

Refinery gas

(1)

(f) Why does kerosene separate out of the mixture before diesel oil?

___________________________________________________________________

___________________________________________________________________(1)

(Total 9 marks)

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Q5.A student investigated the viscosity of liquid hydrocarbons.

A viscous liquid is a liquid that flows slowly.

The student used this method.

• Measure 50 cm3 of the liquid hydrocarbon.

• Pour the liquid hydrocarbon into the funnel, as shown in Figure 1.

• Time how long it takes for all of the liquid hydrocarbon to run out of the funnel.

• Repeat the experiment for other liquid hydrocarbons.

(a) (i) Give the name of apparatus A in Figure 1.

______________________________________________________________(1)

(ii) Name the apparatus that could be used to measure 50 cm3 of liquid hydrocarbon.

______________________________________________________________(1)

(b) The student’s results for six liquid hydrocarbons are shown in Table 1.

Table 1

Formula of liquid hydrocarbon

Time for liquid hydrocarbon to run out of the funnel in seconds Mean time in

secondsExperiment 1 Experiment 2 Experiment 3

C5H12 12 11 13 12

C6H14 14 15 15 15

C7H16 19 20 18

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C8H18 27 26 28 27

C10H22 46 48 47

C12H26 65 67 69 67

(i) The student did the experiment three times with each liquid hydrocarbon.

Give two reasons why.

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________(2)

(ii) Use the data in Table 1 to calculate the mean time, in seconds, for C7H16

______________________________________________________________

______________________________________________________________

Mean time = __________________ seconds(1)

(iii) Complete the sentence.

As the number of carbon atoms in a molecule of liquid hydrocarbon increases, the time taken for the liquid hydrocarbon to run out of the funnel

________________________ .(1)

(iv) A ring has been drawn around one result in Table 1.

This result has not been used to calculate the mean time for C10H22

Suggest why this result was not used.

______________________________________________________________

______________________________________________________________(1)

(v) Suggest one error the student may have made to get the ringed result.

______________________________________________________________

______________________________________________________________

______________________________________________________________(1)

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(c) The student investigated the effect of temperature on the viscosity of one of the liquid hydrocarbons.

The liquid hydrocarbon he was using had the hazard symbols shown in Figure 2.

(i) Suggest why the student warmed the liquid hydrocarbon using warm water and not a Bunsen flame.

______________________________________________________________

______________________________________________________________(1)

(ii) The student wore safety glasses.

Give one other safety precaution the student should take, and give a reason for this safety precaution.

Safety precaution _______________________________________________

Reason _______________________________________________________

______________________________________________________________(2)

(d) This is the method the student used to investigate the effect of temperature on the viscosity of one of the liquid hydrocarbons.

• Measure 50 cm3 of the liquid hydrocarbon and pour it into a beaker.

• Stand the beaker of liquid hydrocarbon in a heated water bath.

• Leave for a few minutes.

• Measure the temperature of the liquid hydrocarbon.

• Pour the liquid hydrocarbon into the funnel, as shown in Figure 3.

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• Time how long it takes for all of the liquid hydrocarbon to run out of the funnel.

• Repeat the experiment at different temperatures.

(i) The student’s results are shown in Table 2.

Table 2

Temperature of liquid hydrocarbon

in °C

Time to run out of the funnel in seconds

23 27

30 21

37 17

46 16

55 11

65 9

Plot the results shown in Table 2 on the graph in Figure 4.

Draw a curve of best fit.

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(3)

(ii) One of the points is anomalous.

Draw a ring around the anomalous point on your graph.(1)

(iii) Predict how long it will take the liquid hydrocarbon to run through the funnel at 70 °C.

Show your working on your graph.

Time = ____________________ seconds(2)

(iv) Describe the relationship between the temperature of the liquid hydrocarbon and the viscosity of the liquid hydrocarbon.

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________(3)

(v) The apparatus the student used in Figure 2 could lead to a systematic error in the results.

Identify one source of systematic error, and describe how the student could avoid or reduce the error.

______________________________________________________________

______________________________________________________________

______________________________________________________________

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______________________________________________________________(2)

(Total 22 marks)

Q6.Crude oil is a fossil fuel.

(a) To make crude oil more useful it is separated into fractions.

Use the correct word from the box to complete each sentence.

boiling compound decomposition distillation

filtration mixture molecule

(i) Crude oil is a _________________________ of different substances.(1)

(ii) The substances in crude oil have different

_________________________ points.(1)

(iii) Crude oil is separated by fractional _________________________ .(1)

(b) Petrol is one of the fractions produced from crude oil.

Car engines use a mixture of petrol and air.

The diagram shows some of the gases produced.

(i) What type of reaction happens to petrol in a car engine?

Tick ( ) one box.

combustion

decomposition

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neutralisation

(1)

(ii) Petrol contains octane (C8H18).

Complete the word equation for the reaction of octane with oxygen.

octane + ______________ ______________ + ______________(2)

(iii) Cars use sulfur-free petrol as a fuel.

Describe why sulfur should be removed from petrol.

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________(2)

(c) Some fractions from crude oil contain large hydrocarbon molecules.

These molecules can be cracked to produce smaller, more useful molecules.

An equation for cracking decane is:

C10H22 C3H8 + C2H4 + C5H10

decane propane ethene pentene

(i) Why is propane useful?

Tick ( ) one box.

Propane is a polymer.

Propane is an alloy.

Propane is a fuel.

(1)

(ii) Draw bonds to complete the displayed structure of ethene.

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(1)

(iii) What is the colour change when bromine water reacts with ethene?

Tick ( ) one box.

Orange to colourless

Orange to green

Orange to red

(1)

(iv) Complete the sentence.

Pentene is useful because many pentene molecules can join together

to form _________________________ .(1)

(Total 12 marks)

Q7.The diagram shows a carbon atom.

(a) (i) A proton is labelled.

Use the correct answer from the box to label each of the other sub-atomic particles.

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electron ion molecule neutron

(2)

(ii) The atom of carbon is represented as:

What is the mass number of this carbon atom?

Draw a ring around the correct answer.

6 13 19(1)

(iii) Complete the sentence.

Atoms of carbon have no overall electrical charge because the number

of protons is the same as the number of _______________________ .(1)

(b) Butane is represented as:

(i) Use the correct answer from the box to complete each sentence.

bond compound helium hydrogen mixture oxygen

Butane is a ___________________ .

Butane contains atoms of carbon and ___________________ .

Each line between the atoms in butane represents a chemical

_________________ .(3)

(ii) Which is the correct formula for butane?

Tick (✔) one box.

C4H4

C4H8

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C4H10

(1)(Total 8 marks)

Q8.Energy is released by burning fuels.

(a) The bar chart shows the energy in kilojoules, kJ, released by burning 1 g of five different fuels.

(i) Which fuel releases least energy by burning 1 g?

______________________________________________________________(1)

(ii) How much energy is released by burning 1 g of coal?

Energy = _________________________kJ(1)

(iii) Calculate the mass of petrol that will release the same amount of energy as 1 g of hydrogen.

Use information from the bar chart to help you.

______________________________________________________________

______________________________________________________________

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Mass = __________________ g(1)

(b) Coal burns in oxygen and produces the gases shown in the table.

Name Formula

Carbon dioxide CO2

Water vapour H2O

Sulfur dioxide SO2

Use information from the table to name one element that is in coal.

___________________________________________________________________(1)

(c) Hydrogen can be made from fossil fuels.Hydrogen burns rapidly in oxygen to produce water only.

A lighthouse uses electricity generated by burning hydrogen.

Suggest two advantages of using hydrogen as a fuel.

Use information from the bar chart and the diagram above to help you.

1. _________________________________________________________________

___________________________________________________________________

2. _________________________________________________________________

___________________________________________________________________(2)

(Total 6 marks)

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Q9.Alkanes are hydrocarbons found in crude oil.

(a) (i) Complete the sentence.

Hydrocarbons contain the elements _____________ and _____________only.

(1)

(ii) Ethane is an alkane with the formula C2H6

Draw a ring around the correct answer to complete the sentence.

Alkanes are hydrocarbons with the general formula

CnHn

CnH2n

CnH2n+2

(1)

(b) Crude oil is separated into useful fractions by fractional distillation.

Describe and explain how crude oil is separated into fractions by fractional distillation.

Use the diagram to help you answer the question.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

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___________________________________________________________________

___________________________________________________________________(4)

(c) Dodecane (C12H26) from crude oil is cracked to produce ethene (C2H4).

(i) Complete the equation for this reaction.

C12H26 2 C2H4 + ______________(1)

(ii) Give two conditions needed for cracking.

1. ____________________________________________________________

2. ____________________________________________________________(2)

(Total 9 marks)

Q10.Barbecues are heated by burning charcoal or burning hydrocarbons.

(a) Use the Chemistry Data Sheet to help you to answer this question.

The chemical equation for charcoal burning is:

C + O2 CO2

Complete the word equation for this reaction.

carbon + __________________ carbon dioxide(1)

(b) Propane is a hydrocarbon.

(i) Complete the displayed structure of propane. Draw in the missing bonds.

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(1)

(ii) Write the chemical formula of propane._________________________(1)

(iii) Draw a ring around the correct answer to complete the sentence.

hydrogen.

Propane burns in air to produce carbon dioxide and hydroxide.

water.

(1)

(c) The table shows information about six hydrocarbons.

Hydrocarbon State at roomtemperature (20°C) Boiling point in °C

Ethane (C2H6) gas −89

Ethene (C2H4) gas −104

Butane (C4H10) gas −1

Butene (C4H8) gas −6

Hexane (C6H14) liquid +69

Hexene (C6H12) liquid +64

Tick ( ) two correct statements about the six hydrocarbons.

Statement Tick ( )

Ethane and butane boil at temperatures less than 20°C.

Hexene and butene are alkanes.

Butane and hexane are liquid at 0°C.

Ethene and hexene each have a carbon-carbon double bond.

(2)(Total 6 marks)

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Q11.(a) Crude oil is a mixture of compounds.

These compounds are made up of hydrogen and carbon atoms only.

(i) Draw a ring around the correct answer to complete the sentence.

Compounds made up of carbon and hydrogen atoms only

alcohols.

are called hydrocarbons.

vegetable oils.

(1)

(ii) The table shows five of these compounds.

Compound State at room temperature (20 °C) Boiling point in °C

ethane, C2H6 gas – 89

butane, C4H10 gas 0

hexane, C6H14 liquid +69

pentadecane, C15H32 liquid +270

heptadecane, C17H36 solid +302

Tick ( ) two correct statements about the five compounds.

Statement Tick ( )

ethane has the smallest molecules

hexane and pentadecane are liquid at 100 °C

heptadecane has the highest boiling point

butane boils at 100 °C

(2)

(iii) Draw a ring around the correct answer to complete each sentence.

Fractional distillation is used to separate the compounds in crude oil.

cracking

The first step in fractional distillation is displacing the crude oil.

evaporating

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burn

During fractional distillation the compounds

condense

decompose

at different temperatures.(2)

(b) Steam distillation is used to separate oils from plants.

The diagram shows some apparatus that can be used to separate oil from lavender plants. Four parts of the apparatus are labelled W, X, Y and Z.

(i) In which part, W, X, Y or Z, of the apparatus:

is steam produced

are steam and oil condensed?

(2)

(ii) Use the correct word from the box to complete the sentence.

dissolves floats sinks

When the oil separates from the water, the oil ___________________(1)

(iii) Describe how part Z of the apparatus can be used to remove the water from the oil.

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______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________(2)

(Total 10 marks)

Q12.About 3000 million years ago carbon dioxide was one of the main gases in the Earth’s early atmosphere.

About 400 million years agoplants and trees grew on mostof the land. When the plantsand trees died they werecovered by sand and slowlydecayed to form coal.

Today coal is burned in powerstations to release the energyneeded by industry.

(a) The bar chart shows the percentage of some of the elements in this coal.

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(i) This coal contains 85 % carbon. Draw the bar for carbon on the chart.(1)

(ii) Coal is burned in the atmosphere to release energy.Two of the products of burning coal are shown.

Draw one line from each product to its environmental impact.

Product Environmental impact

Acid rain

Sulfur dioxide

Global dimming

Carbon particles

Global warming

(2)

(b) Use the information above and your knowledge and understanding to answer these questions.

(i) How did the formation of coal decrease the amount of carbon dioxide in the Earth’s early atmosphere?

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______________________________________________________________

______________________________________________________________(1)

(ii) How does burning coal affect the amount of carbon dioxide in the Earth’s atmosphere?Explain your answer.

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________(2)

(Total 6 marks)

Q13.Crude oil is a mixture of hydrocarbons.Crude oil can be separated into fractions.

(a) (i) Complete the sentence.

The process used to separate the crude oil into fractions is called

fractional ______________________________ .(1)

(ii) Why do the fractions separate at different temperatures?

______________________________________________________________

______________________________________________________________(1)

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(b) Tick ( ) two properties of fraction 6.

Property Tick ( )

contains hydrocarbons

has a small number of carbon atoms in each molecule

is easy to ignite

has a high boiling point

(2)

(c) Fraction 1 contains hydrocarbons called alkanes.The general formula of an alkane is: CnH2n+2

What is the formula of the alkane that has 5 carbon atoms in each molecule?

Draw a ring around the correct answer.

C5H9 C5H10 C5H11 C5H12

(1)(Total 5 marks)

Q14.Natural gas is mainly a hydrocarbon called methane.

(a) Use one word from the box to complete the sentence.

compounds elements molecules

Hydrocarbons contain hydrogen and carbon only.

Hydrogen and carbon are _____________________________________________ .(1)

(b) The diagrams represent atoms of hydrogen and carbon.

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Draw a ring around the correct answer to complete the sentences.

bond.

(i) The centre of each atom is called the nucleus.

symbol.

(1)

three

(ii) The hydrogen atom has one electron and the carbon atom has four electrons.

six

(1)

(c) A molecule of methane can be represented as

Draw a ring around the correct answer to complete the sentences.

CH

(i) The formula of methane is CH4

C4H4

(1)

bond.

(ii) The line between C—H is called a molecule.

nucleus.

(1)

(d) Methane burns to produce carbon dioxide (CO2) and water (H2O).

(i) Draw a ring around the correct answer to complete the sentence.

carbon.

When methane burns it reacts with nitrogen.

oxygen.

(1)

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(ii) Hydrogen (H2) can be used as a fuel.

Suggest why burning hydrogen would be less harmful to the environment than burning methane.

______________________________________________________________

______________________________________________________________(1)

(Total 7 marks)

Q15.Crude oil is a natural resource from which useful fuels can be separated.

(a) Crude oil is a mixture of hydrocarbons.

Complete the sentence about a hydrocarbon molecule.

A hydrocarbon molecule is made up of ____________________ and carbon atoms only.

(1)

(b) Many fuels come from crude oil. Some of these fuels are shown in the diagram.

Suggest two properties of these fuels that allow them to be separated from crude oil.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________(2)

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(c) Fuels from crude oil burn to provide heat energy.

When a fuel burns, it combines with oxygen in the air and produces carbon dioxide and water. When there is not enough oxygen, the fuel burns and also produces carbon monoxide and carbon particles.

Draw a straight line from each substance that links it to a possible environmental problem.

One has been done for you.

(3)

(Total 6 marks)

Q16.(a) Complete this sentence about crude oil.

Crude oil is mainly a mixture of compounds called ___________________ which contain carbon and hydrogen only.

(1)

(b) The diagram shows a laboratory experiment used to separate crude oil.

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Complete each sentence by choosing the correct words from the box.

condensation distillation evaporation

melting sublimation

The main process taking place at A is _________________________________

The main process taking place at B is _________________________________

This method of separating crude oil is called ____________________________(3)

(c) Complete this sentence by crossing out the word in each box that is wrong. The first one has been done for you.

This method of separating crude oil works because the the molecules are,

the their boiling point and the volatile they are.(1)

(Total 5 marks)

Q17.Petrol is a hydrocarbon fuel.

(a) Complete this sentence.

Hydrocarbons are compounds which are made from the elements _____________

and ____________________ only.

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(2)

(b) This apparatus was used to study the combustion of a hydrocarbon fuel.

(i) Name the substance which changed the anhydrous copper sulphate from white to blue.

______________________________________________________________(1)

(ii) Carbon dioxide is also produced when the hydrocarbon fuel is burned.Name the solution, labelled X on the diagram, which tests for carbon dioxide.

______________________________________________________________(1)

(iii) Complete this sentence.

Carbon dioxide turns solution X ______________________________________ .(1)

(c) The graph shows how the concentration of carbon dioxide in the air has varied since the year 1000.

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(i) Describe the changes in the concentration of carbon dioxide in the air since the year 1000.

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________(3)

(ii) Suggest why the concentration of carbon dioxide in the air has changed since the year 1800.

______________________________________________________________

______________________________________________________________(1)

(Total 9 marks)

Q18.Some gas cookers burn natural gas, methane. Methane, CH4, is a hydrocarbon.

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(a) What is meant by hydrocarbon?

___________________________________________________________________

___________________________________________________________________(2)

(b) When methane burns there must be a good supply of air.

(i) Complete the word equation by choosing the correct two chemicals from the box.

carbon dioxide hydrogen oxygen water

methane + oxygen → ____________________ + ______________________(2)

(ii) Without a good supply of air, carbon monoxide is formed. Why is carbon monoxide a dangerous gas?

______________________________________________________________

______________________________________________________________(1)

(Total 5 marks)

Q19.Fractional distillation is used to separate fractions in the crude oil mixture.

(a) Draw a line to join each fraction to its use as a fuel. One line has been drawn for you.

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(2)

(b) (i) Why does petrol separate from the other fractions in the crude oil mixture?

______________________________________________________________

______________________________________________________________(1)

(ii) Petrol contains the elements carbon and hydrogen only.

Which two of the substances in the diagram are formed when petrol burns?

1. ____________________________________________________________

2. ____________________________________________________________(2)

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(Total 5 marks)

Q20.The table shows some information about alkanes.

Name Formula Relative formula mass Boiling point in °C

methane CH4 16 –160

ethane C2H6 30 –90

propane 44 –40

butane C4H10 58

pentane C5H12 72 36

hexane C6H14 86 68

(a) Give the formula of propane.

___________________________________________________________________(1)

(b) (i) What happens to the boiling points of the alkanes as the relative formula mass increases?

______________________________________________________________(1)

(ii) Draw a graph. Plot the points and draw a best fit line.

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(3)

(iii) What is the boiling point of butane?

______________________________________________________________(1)

(iv) Show clearly on the graph how you found the boiling point of butane.(1)

(c) Circle which of the following is not an alkane.

C71116 C9H18 C11H24 C24H50

(1)(Total 8 marks)

Q21.Hot air balloons are used mainly for pleasure trips.

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(a) Air is a mixture of gases. Complete the table. (Carbon dioxide has been done for you.)

Gas Chemical formula % in air

nitrogen 78

oxygen O2

argon 0.9

carbon dioxide CO2 0.03

(3)

(b) The air in the balloon is heated using a propane burner. Propane, C3H8, is a hydrocarbon that burns in air forming carbon dioxide, CO2, and water, H2O.

(i) What does hydrocarbon mean?

______________________________________________________________

______________________________________________________________(1)

(ii) Which gas, in the air, reacts with propane when it burns?

______________________________________________________________(1)

(iii) What type of chemical reaction happens when a hydrocarbon burns?

______________________________________________________________(1)

(iv) The formation of more carbon dioxide causes global problems. Explain why.

______________________________________________________________

______________________________________________________________

______________________________________________________________

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______________________________________________________________(2)

(Total 8 marks)

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gcseprep.com · web view4/7/2020 · when a fuel burns, it combines with oxygen in the air and...

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