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11 1 C1 Exam Revision (Higher)

C1.1 The fundamental ideas in Chemistry Revision Questions

Q1. A substance made of only one type of atom is called an element.

The chemical symbols and positions of six elements in the periodic table are shown.

Draw a straight line from each description to its correct symbol.

Description Symbol

Al

A metal with a low density that does not corrode easily

Fe

It has properties similar to those of sodium, Na

He

It is a transition metal

Li

It is a noble gas

O

(Total 4 marks)

Q2. The diagram shows an atom.

(a) On the diagram, write the names of structures A, B, C and D. (4)

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(b) To which Group of the periodic table does this atom belong?

.....................................................................................................................................

Give one reason for your answer.

..................................................................................................................................... (2)

(c) Name the element which is made up of this type of atom.

..................................................................................................................................... (1)

Q3. There are millions of different substances that make up our world. All these substances are made from chemical elements.

(a) What is an element?

..................................................................................................................................... (1)

(b) Many substances are compounds. What is a compound?

.....................................................................................................................................

..................................................................................................................................... (2)

Q4. Atoms are made up of three main particles called protons, neutrons and electrons. Use the periodic table on the data sheet to help you to answer these questions.

(a) Sodium is in Group 1 of the periodic table.

(i) Why are potassium and sodium in the same Group of the periodic table?

............................................................................................................... (1)

(ii) How many protons are in an atom of sodium? ..................................... (1)

(iii) The atomic number of sodium is 11. How many neutrons are in an atom of sodium with mass number 23?

...................................... (1)

(iv) Each sodium atom has 11 electrons. Complete the electronic structure of sodium.

(2)

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(b) The chemical equation for a reaction of sodium is shown below.

2Na + Cl2 → 2NaCl

Describe this reaction of sodium in terms of the names of the substances and the numbers of the atoms involved.

........................................................................................................................

........................................................................................................................ (3)

Q5. This question is about oxygen atoms. The periodic table on the Data Sheet may help you to answer this question.

(a) (i) Oxygen atoms have 8 electrons. Complete the diagram to represent the arrangement of electrons in an oxygen atom. Use crosses (×) to represent the electrons.

(1)

(ii) Name the part of the oxygen atom that is labelled A on the diagram.

........................................................................................................................... (1)

(b) Two isotopes of oxygen are oxygen-16 and oxygen-18.

16 18

O O 8 8

oxygen-16 oxygen-18

Explain, in terms of particles, how the nucleus of an oxygen-18 atom is different from the nucleus of an oxygen-16 atom.

.....................................................................................................................................

..................................................................................................................................... (2)

Q6. The diagram shows the reaction of hydrogen molecules with oxygen molecules to form water molecules.

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(i) In the empty box draw one oxygen molecule. (1)

(ii) Why are hydrogen and oxygen called elements?

..................................................................................................................................... (1)

(iii) Why is water called a compound?

.....................................................................................................................................

..................................................................................................................................... (2)

Q7. The picture shows sodium reacting with chlorine. The reaction forms sodium chloride.

(a) Use words from the box to answer the questions.

compound element hydrocarbon mixture

Which word best describes:

(i) sodium ....................................................................... (1)

(ii) sodium chloride? ........................................................ (1)

(b) When sodium reacts with chlorine the sodium atoms change into sodium ions. The diagrams below represent a sodium atom and a sodium ion.

Use the diagrams to help you explain how a sodium atom turns into a sodium ion.

........................................................................................................................

........................................................................................................................

........................................................................................................................ (2)

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(c) (i) The diagram below represents a chlorine atom.

When chlorine reacts with sodium the chlorine forms negative chloride ions.

Complete the diagram below to show the outer electrons in a chloride ion (Cl–).

(1)

(ii) Chloride ions are strongly attracted to sodium ions in sodium chloride.

Explain why.

............................................................................................................... (1)

Q8. This barbecue burns propane gas.

The diagram represents a propane molecule.

(a) What is the formula of propane? ........................................................................................ (1)

(b) (i) Draw a ring around the name of the particle represented by the symbols ○ and × in the diagram.

electron neutron proton (1)

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(ii) Draw a ring around the type of bonding that holds the atoms together in a propane molecule.

covalent ionic metallic (1)

(c) Under high pressure in the cylinder propane is a liquid. Liquid propane evaporates easily to form a gas when the tap on the cylinder is opened. Draw a ring around the correct answer in each box to explain why propane evaporates easily.

Propane has a high

low boiling point because it consists of

large

small molecules.

(1)

Q9. (a) Atoms are made of sub-atomic particles. Complete the six spaces in the table

Name of sub-atomic particle Relative mass Relative charge

.................................

......................

Neutron ..................... .......................

................................. 1 .......................

(3)

(b) Complete the spaces in the sentences.

(i) The atomic number of an atom is the number of ..................................... in its

nucleus and is equal to the number of ...................................................... (1)

(ii) The mass number of an atom is the total number of ................................. and

...................................... in its nucleus. (1)

(c) The table gives information about the atoms of three elements.

Name of element

Chemical symbol

Number of electrons in:

1st

shell 2nd

shell 3rd

shell

Fluorine F 2 7 0

Neon Ne 2 8 0

Sodium Na 2 8 1

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Two of these elements can react together to form a chemical compound.

(i) What is the name and the formula of this compound?

Name ................................................... Formula .......................................... (2)

(ii) What type of bonding holds this compound together?

........................................................................................................................... (1)

(iii) Explain, in terms of electron transfer, how the bonding occurs in this compound.

...........................................................................................................................

........................................................................................................................... (2)

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C1.2 Limestone and Building Materials Questions Higher

Q1. Limestone and the products of limestone have many uses.

(a) Limestone is quarried.

Photograph © Lonny Kalfus / Getty Images

Quarrying limestone has impacts that cause environmental problems.

Tick ( ) two impacts that cause environmental problems.

Impact of quarrying Tick ( )

Puts off tourists

Causes dust pollution

Increases jobs

Increases traffic

(2)

(b) Limestone contains calcium carbonate, CaCO3. When it is heated calcium carbonate produces calcium oxide and carbon dioxide.

The word equation for this reaction is:

calcium carbonate → calcium oxide + carbon dioxide

(i) Complete the sentence.

The reaction when calcium carbonate is heated is called

thermal ........................................... (1)

(ii) 100 g of calcium carbonate was heated and produced 56 g of calcium oxide. Calculate the mass of carbon dioxide produced.

...............................................................................................................

....................................... g (1)

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(c) The flow chart shows the stages in the limestone cycle.

Complete the names of the calcium compounds formed in the flow chart.

(2)

Q2. Limestone has been called the Earth’s most useful rock.

(a) Limestone contains calcium carbonate, CaCO3.

(i) Complete the table to show the number of atoms of each element in the formula of calcium carbonate. Calcium has been done for you.

Element Number of atoms in the formula CaCO3

Calcium, Ca 1

Carbon, C

Oxygen, O

(2)

(ii) The diagram below represents a carbon atom. Use words from the box to label the parts of this atom.

bond electron molecule nucleus

(2)

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(b) At a cement works, limestone is mixed with clay and heated in a kiln.

Use the information in the diagram to answer these questions.

(i) Name the fuel that is used to heat the limestone and clay.

........................................................................................................................... (1)

(ii) Limestone contains calcium carbonate, CaCO3 Draw a ring around the correct gas in the box to complete the sentence.

The gas formed when calcium carbonate decomposes is

argon.

carbon dioxide.

nitrogen.

(1)

(c) The cement works starts to burn a different fuel. Local residents are concerned because more children are suffering asthma attacks. Residents have also noticed that parked cars are becoming dirty because of smoke particles from the chimney. The table shows the possible medical risk from smoke particles.

Particle size in mm Medical effect

Larger than 0.4 No medical risks known

0.3 and smaller Causes asthma attacks

0.2 and smaller May cause cancer

(i) Give two reasons why local residents are concerned about the cement works burning a different fuel.

1 ........................................................................................................................

2 ........................................................................................................................ (2)

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(ii) The company operating the cement works stated that smoke particles from the chimney had not changed since it started burning the different fuel.

If you were a local resident, what evidence would you like to see to help you decide if the company’s statement is true or not?

...........................................................................................................................

........................................................................................................................... (2)

Q3. A limestone quarry is in an area of natural beauty and near several villages. The company operating the quarry wants planning permission to build a new cement works in the quarry. The diagram shows some of the substances used and produced at a cement works.

(a) Limestone is mainly calcium carbonate, CaCO3. Write the correct number in the box to complete each sentence.

(i) The formula shows that calcium carbonate, CaCO3,

contains different elements. (1)

(ii) Calcium carbonate, CaCO3, contains a total number of atoms. (1)

(b) The company wants the new cement works because the nearest cement works is 100 km from the quarry. The company argues that a new cement works sited inside the quarry would reduce carbon dioxide emissions.

Suggest why the new cement works might reduce carbon dioxide emissions.

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (1)

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(c) Residents from the villages near the quarry are concerned that there will be atmospheric pollution from the new cement works.

(i) Name and explain how one of the emissions from the chimney causes atmospheric pollution.

Name of emission: ...........................................................................................

Explanation: ..................................................................................................... (2)

(ii) Suggest what the company could do to reduce this atmospheric pollution.

........................................................................................................................... (1)

Q4. Sea water contains magnesium ions. Magnesium oxide can be obtained from sea water using the following process.

(a) State the chemical name for limestone.

.................................................................................................................................... (1)

(b) Write a word equation for the action of heat on limestone.

.................................................................................................................................... (2)

(c) State the chemical name for slaked lime.

.................................................................................................................................... (1)

(d) Write a balanced chemical equation for the addition of water to quicklime.

................................................................................................................................... (2)

(e) How can magnesium hydroxide be separated from sea water?

................................................................................................................................... (1)

(f) Suggest and explain how magnesium could be obtained from magnesium oxide.

...................................................................................................................................

................................................................................................................................... (2)

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Q5. Portland cement was invented by Joseph Aspdin, a builder from Leeds. The flow diagram shows how cement is made.

(a) What are the two raw materials used to make cement?

1 .....................................................................

2 ..................................................................... (1)

(b) Cement is mixed with three substances to make concrete. Choose from the list the three substances used.

crushed rock iron ore quicklime sand

slag soda water

1 .....................................................................

2 .....................................................................

3 ..................................................................... (3)

Q6. (a) Limestone is a hard rock that is used as a building material. Limestone was used by the Egyptians to make plaster.

Reaction 1 – calcium carbonate, CaCO3, was decomposed by heating limestone

CaCO3 → CaO + CO2

Reaction 2 – water was added to the solid produced to make slaked lime

CaO + H2O → Ca(OH)2

Reaction 3 – a mixture of slaked lime and water was used as plaster. After the plaster had set it became even harder with age

Ca(OH)2 + CO2 → CaCO3 + H2O

(i) Name the solid formed when calcium carbonate decomposed.

........................................................................................................................... (1)

(ii) Use the reactions to explain how the plaster became even harder with age.

...........................................................................................................................

...........................................................................................................................

...........................................................................................................................

........................................................................................................................... (3)

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(b) A gardener wanted to make a step up to his greenhouse door. He decided to use a mixture of cement and sand to make mortar.

He experimented using mixtures with different cement to sand ratios.

• The mortar mixtures were put in the same sized mould.

• Each mortar mixture was allowed to set hard.

• He then dropped a metal ball from increasing heights until the set mortar cracked.

• He recorded his results in a table.

Volume of sand in cm3

Volume of cement in cm3

Height the metal ball dropped to crack the set mortar in cm

800 100 17

700 100 24

600 100 30

500 100 36

400 100 37

300 100 48

200 100 54

(i) What is the relationship between the volume of sand and the strength of the mortar?

........................................................................................................................... (1)

(ii) The gardener was not sure about some of his results. Use the results to explain why.

...........................................................................................................................

........................................................................................................................... (2)

Q7. Portland cement was invented by Joseph Aspdin, a builder from Leeds. The flow diagram shows how cement is made.

(a) (i) Name the raw material X used to make cement.

.......................................................................................................................... (1)

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(ii) In the kiln the raw materials are heated to about 1500°C. The limestone (calcium carbonate) is broken down at this temperature. Complete the word equation for this reaction.

calcium carbonate → ........................................ + carbon dioxide (1)

(iii) Suggest one major cost of this process other than the cost of the raw materials.

.......................................................................................................................... (1)

(b) Cement can be used to make concrete. Name two substances that must be mixed with cement to make concrete.

1 .....................................................................

2 ..................................................................... (2)

(Total 5 marks)

Q8. Limestone is an important raw material.

The diagram shows a lime kiln. The limestone is heated by the burning coal.

(i) Suggest why hot air is blown into the lime kiln.

.....................................................................................................................................

(1)

(ii) Give two reasons why carbon dioxide is produced in the lime kiln.

Reason 1 .....................................................................................................................

.....................................................................................................................................

Reason 2 .....................................................................................................................

..................................................................................................................................... (2)

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C1.3 Metals and their uses Revision Questions Higher

Q1. Iron is the main structural metal used in the world.

(a) The diagram represents the particles in iron, Fe.

Draw a ring around the correct word in the box to complete the sentence.

Iron is described as an element because all the

atoms

compounds

metals

are the same.

(1)

(b) Stainless steel is mostly iron.

The diagram represents the particles in stainless steel.

Use the correct words from the box to complete the sentences about alloys.

metal mixture molecule polymer smart structure

Stainless steel is an alloy because it is a ........................................................................... of iron, chromium and nickel. An alloy is made up of more than one type of ................................................................ . Stainless steel alloys are harder than iron because the different sized atoms added change the ............................................................................... . An alloy that can return to its original shape after being deformed is called a..................................................................... alloy.

(4)

(c) In the UK, we use about 1.8 billion steel cans every year but only 25% are recycled. Used steel cans are worth about £100 per tonne.

Recycling saves raw materials and reduces waste that would end up in landfill. Producing steel by recycling used cans saves 75% of the energy that would be needed to produce steel from iron ore. This also reduces carbon dioxide emissions.

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(i) Give two reasons, from the information above, to explain why recycling used steel cans is a good idea.

1 ........................................................................................................................

2 ........................................................................................................................ (2)

(ii) Suggest how the local council could increase the percentage of used steel cans that are recycled.

........................................................................................................................... (1)

Q2. Iron ore is the main source of iron.

(a) This was the headline in a newspaper.

‘Village protests against quarry’

The dotted line ( ---- ) on the map is drawn around the area from which a company

wants to quarry iron ore.

(i) Give one reason that the company could give for the need to quarry the iron ore.

.......................................................................................................................... (1)

(ii) The people who live in the village do not want the quarry because it would decrease the value of their homes.

Suggest two other reasons why the villagers do not want the quarry.

1 .......................................................................................................................

2 ....................................................................................................................... (2)

(b) Iron ore contains the compound iron oxide, Fe2O3.

(i) Iron is extracted from its oxide in the blast furnace.

Complete the word equation for the extraction of iron.

iron oxide + ............................................................... → iron + carbon dioxide (1)

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(ii) This diagram represents pure iron.

Use the diagram to explain why pure iron is described as an element.

..........................................................................................................................

.......................................................................................................................... (2)

(iii) Pure iron is relatively soft. The iron from the blast furnace is hard and brittle. The diagram below represents iron from the blast furnace.

Use the diagram to explain why iron from the blast furnace is hard and brittle.

.......................................................................................................................... (2)

Q3. Copper metal is used for electric wires. An alloy of copper, called brass, is used for pins and terminals of electric plugs.

(a) Copper metal is relatively soft and flexible.

Give another reason why copper is used for electric wires.

.................................................................................................................................... (1)

(b) Brass is an alloy.

What is an alloy?

.................................................................................................................................... (1)

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(c) Open-cast mining of copper ore makes a very large hole.

(i) Suggest one environmental problem that is caused by open-cast mining of copper ore.

.......................................................................................................................... (1)

(ii) Some copper ores contain copper sulfide, CuS.

Copper sulfide is heated in air to produce copper and sulfur dioxide.

CuS + O2 → Cu + SO2

Suggest one environmental problem caused by heating copper sulfide in air.

.......................................................................................................................... (1)

(d) The amount of copper-rich ores is estimated to last only a few more years. New houses need several kilometres of copper wire.

(i) Explain why the need to use so much copper will cause a problem in the future.

.......................................................................................................................... (1)

(ii) Suggest two ways in which society could overcome this problem.

1 .......................................................................................................................

2 ....................................................................................................................... (2)

Q4. Metals and their alloys have many uses.

(a) Dentists use a smart alloy to make braces that gently push teeth into the right position.

What is meant by a smart alloy?

.................................................................................................................................... (1)

(b) Pure copper is made up of layers of copper atoms. Brass is an alloy of copper and zinc.

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Why are the physical properties of brass different from the physical properties of pure copper?

....................................................................................................................................

.................................................................................................................................... (2)

(c) Nearly all zinc is obtained from ores that also contain lead. The metals zinc and lead can be extracted by reducing their oxides using carbon.

(i) Choose one element from the box below to complete the sentence about the reduction of zinc oxide.

lead nitrogen oxygen

Zinc oxide is reduced by carbon, which takes away.................................................. to leave zinc metal.

(1)

(ii) The melting points and boiling points of lead and zinc are given in the table.

Metal Lead Zinc

Melting point in °C 328 420

Boiling point in °C 1740 907

The furnace operates at a temperature of 1200 °C.

Suggest how the lead metal and zinc metal are separated in the furnace.

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (2)

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Q5. The table gives information about some metals.

Name of the metal Cost of one tonne of the metal in December 2003 (£)

Percentage of the metal in the crust of the earth (%)

Aluminium 883 8.2

Platinum 16720000 0.0000001

Iron 216 4.1

Gold 8236800 0.0000001

(a) Use information in the table to suggest why gold and platinum are very expensive metals.

..................................................................................................................................... (1)

(b) Aluminium and iron are made by reduction of their ores.

(i) Name the element that is removed from the ores when they are reduced.

........................................................................................................................... (1)

(ii) Use the reactivity series on the Data Sheet to suggest a metal that would reduce aluminium ore.

........................................................................................................................... (1)

(c) Aluminium is made by the reduction of molten aluminium ore, using a very large amount of electricity.

(i) How is iron ore reduced in a blast furnace to make iron?

...........................................................................................................................

........................................................................................................................... (2)

(ii) Suggest why aluminium is more expensive than iron.

........................................................................................................................... (1)

Q6. A student was trying to extract the metals from lead oxide and aluminium oxide. She heated each oxide with carbon in a fume cupboard as shown below.

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She was able to extract lead from lead oxide but not aluminium from aluminium oxide.

(i) Explain the results of these experiments.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

(ii) Complete this word equation for the reaction between lead oxide and carbon.

lead oxide + carbon → .................................... + ....................................... (Total 5 marks)

Q7. (a) Aluminium is more expensive than iron. Why is aluminium and not iron used for the central core in power cables?

....................................................................................................................................

.................................................................................................................................... (2)

(b) Many industrial processes involve the removal of minerals by quarrying.

All quarrying has some effect on the environment and on people’s lives. Make comments about the social, economic, health, safety and environmental effects of quarrying.

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

.................................................................................................................................... (5)

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Q8. Use the Reactivity Series of Metals on the Data Sheet to help you to answer this question. The table gives information about the extraction of some metals.

Metal Date of discovery Main source Main extraction method

Gold Known to ancient civilisations

In the Earth as the metal itself

Physically separating it from the rocks it is mixed with

Zinc 1500 Zinc carbonate Reduction by carbon

Sodium 1807 Sodium chloride Electrolysis

(a) Explain why gold is found mainly as the metal itself in the Earth.

..................................................................................................................................... (1)

(b) One of the reactions involved in producing zinc is represented by this equation.

ZnO + C → Zn + CO

Explain why carbon can be used to extract zinc.

..................................................................................................................................... (1)

(c) Sodium is one of the most abundant metals on Earth.

Explain, as fully as you can, why sodium was not extracted until 1807.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (2)

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C1.4 Crude oil and fuels Revision Questions Higher

Q1. Crude oil is a mixture of many saturated hydrocarbons. They can be separated into fractions by the process of fractional distillation.

State what is meant by:

(i) hydrocarbon. ............................................................................................................

.................................................................................................................................... (2)

(ii) saturated. .................................................................................................................. (1)

(iii) fraction. .................................................................................................................... (1)

Q2. Crude oil contains many different hydrocarbons.

(i) Which formula in the list represents a hydrocarbon? Draw a ring around the correct formula.

CO2 C6H12O6 C8H18 H2O (1)

(ii) Which word from the list below best describes crude oil? Draw a ring around the correct word.

alloy compound element mixture (1)

(iii) Choose, from the list below, words to complete the passage about the separation of the hydrocarbons in crude oil by fractional distillation.

atoms burned condensed evaporated filtered

fractions ions molecules neutralised

During fractional distillation the many hydrocarbons in crude oil are separated into ................................. each of which contains ................................ with a similar number of carbon .................................... . To do this the oil is first .................................... and then .................................... at a number of different temperatures.

(5)

Q3. The structural formulae of two saturated hydrocarbons are shown below.

Describe two ways in which they will differ in their physical properties.

1 .................................................................................................................................

2 ................................................................................................................................. (Total 2 marks)

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Q4. Crude oil is a complex mixture of hydrocarbons, mainly alkanes. The number of carbon atoms in the molecules ranges from 1 to over 100.

(a) How does the boiling point change as the number of carbon atoms in the molecules increases?

..................................................................................................................................... (1)

(b) Name the method used to separate petroleum into fractions.

..................................................................................................................................... (1)

(c) The simplest hydrocarbon is methane, CH4. Its structure can be represented:

Draw the structure of ethane, C2H6. (1)

Q5. Useful fuels can be produced from crude oil. Crude oil is a mixture of hydrocarbons.

(a) The table shows the boiling points of four of these hydrocarbons.

Hydrocarbon Boiling point in °C

methane, CH4 –162

butane, C4H10 0

pentane, C5H12 +36

decane, C10H22 +175

Tick ( ) two statements that are correct about these hydrocarbons.

Statement Tick ( )

decane has the largest molecules

pentane is a liquid at 40°C

methane and butane are gases at 20°C

methane has the highest boiling point

butane does not boil

(2)

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(b) Natural gas supplied to homes and schools is mainly methane. The diagram shows an apparatus to investigate the two substances produced when natural gas burns completely in air.

(i) Name the liquid that collects in the U-tube. ........................................ (1)

(ii) Name the gas that turns the limewater cloudy .................................... (1)

(c) Some crude oil contains sulfur. Petrol and diesel fuels are produced from crude oil.

The sulfur must be removed from these fuels before they are burned. Explain why.

........................................................................................................................ (2)

Q6. (a) Some hydrocarbons are used as fuels in power stations. The table gives the boiling points of four hydrocarbons.

Hydrocarbon Boiling point

in °C

W 165

X –160

Y –40

Z 180

(i) Which of these hydrocarbons are gases at room temperature (20 °C)?

........................................................................................................................... (1)

(ii) Which of these hydrocarbons has the largest molecules?

........................................................................................................................... (1)

(iii) Which of these hydrocarbons ignites most easily?

........................................................................................................................... (1)

(b) Some hydrocarbons are used to produce polymers. Which type of hydrocarbons can be converted into polymers?

........................................................................................................................... (1)

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Q7. The table shows how much carbon dioxide is produced when you transfer the same amount of energy by burning coal, gas and oil.

(a) Use the information from the table to complete the bar-chart. (3)

(b) The second bar-chart shows how much sulphur dioxide is produced by burning the same three fuels.

Compare the amount of sulphur produced by burning gas with the amount produced by burning coal.

.....................................................................................................................................

..................................................................................................................................... (2)

(c) (i) Coal and oil produce carbon dioxide and sulphur dioxide when they burn. What elements must they contain?

........................................................................................................................... (2)

(ii) Burning fuels also produce nitrogen oxides, even though the fuels contain no nitrogen. Explain why this happens.

...........................................................................................................................

........................................................................................................................... (2)

(Total 9 marks)

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Q8. Crude oil is a mixture of long-chain hydrocarbons. It is cracked to produce a mixture of smaller alkanes and alkenes. Among the gases formed are ethane and ethene.

(a) Write the structural formula for:

(i) ethane

(1)

(ii) ethene

(1)

(iii) Give an example of one chemical reaction which both ethane and ethene undergo.

........................................................................................................................... (1)

(iv) Describe how to distinguish between ethane and ethene. Include a description of the practical method you would use and what you would expect to observe.

...........................................................................................................................

...........................................................................................................................

........................................................................................................................... (3)

(b) Ethene may be polymerised to form a polymer. Give the name of the polymer and a use for it.

Name ............................................... Use ........................................................... (1)

Q9. Since 2000 there has been a lot more research into alternative, environmentally-friendly fuels for road transport. Several pollutants are found in the exhaust emissions produced when fossil fuels are used for road transport. Carbon monoxide (CO) interferes with the way that red blood cells carry oxygen. Carbon dioxide (CO2) increases the level of carbon dioxide in the atmosphere and causes global warming. Oxides of nitrogen (NOx) are produced at high temperatures when nitrogen and oxygen from the atmosphere combine. Sulfur dioxide (SO2) is produced when sulfur impurities in the fuel combine with oxygen in the atmosphere.Tiny particles of solids are produced when the fuel does not burn completely. This increases the level of particulates (PM10) in the atmosphere.

(a) Name the environmental effect caused by:

(i) oxides of nitrogen (NOx) and sulfur dioxide (SO2)

.......................................................................................................................... (1)

(ii) the increased level of particulates (PM10).

.......................................................................................................................... (1)

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(b) Diesel obtained from crude oil is often called fossil diesel. Biodiesel can be made from many vegetable oils. One research project compared the exhaust emissions when fossil diesel or biodiesel were used as fuels.

Some of the relative amounts of these exhaust emissions are shown in the bar chart.

(i) Use your knowledge and the information above to explain the environmental benefits of using biodiesel as a sustainable, low pollution fuel.

...........................................................................................................................

...........................................................................................................................

...........................................................................................................................

...........................................................................................................................

...........................................................................................................................

........................................................................................................................... (3)

(ii) Biodiesel is called a green fuel.

This is because the life-cycle emission of carbon dioxide from biodiesel is less than that from fossil diesel.

Use your knowledge and the information above to explain why biodiesel’s contribution to global warming is considered to be much less than that of fossil diesel.

...........................................................................................................................

...........................................................................................................................

...........................................................................................................................

...........................................................................................................................

...........................................................................................................................

........................................................................................................................... (3)

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C1.5 Useful products from crude oil Revision Higher

Q1. Crude oil is a resource from which fuels can be separated.

(a) The name of the main fuel fractions and one of the hydrocarbons in each fraction are shown in the table.

(i) How does the number of carbon atoms in a hydrocarbon affect its boiling point?

........................................................................................................................... (1)

(ii) Suggest the lowest temperature to which crude oil needs to be heated to vaporize all the hydrocarbons in the table.

Temperature = ................................................ °C (1)

(iii) Dodecane boils at 216 °C. At what temperature will dodecane gas condense to liquid?

Temperature = ................................................ °C (1)

(b) The bar chart shows the relative supply and demand for the petrol and diesel fractions.

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(i) How does the relative supply and demand for petrol and diesel fractions cause problems for an oil company?

...........................................................................................................................

...........................................................................................................................

........................................................................................................................... (2)

(ii) Suggest one way an oil company could solve these problems.

...........................................................................................................................

........................................................................................................................... (1)

(Total 6 marks)

Q2. The diagram shows an apparatus that can be used to carry out cracking reactions in a laboratory.

(a) Why is aluminium oxide or broken porcelain used?

..................................................................................................................................... (1)

(b) Paraffin contains decane. The cracking of decane can be represented by the equation below. A decane molecule is split into two smaller molecules.

Complete the equation by adding the formula of the other product.

C10H22 (l) →.................... (l) + C2H4 (g) decane

(1)

(c) Would you expect C2H4 molecules to collect at position A or B shown on the diagram?

Position ............................

Explain your answer.

..................................................................................................................................... (1)

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(d) Cracking reactions involve thermal decomposition.

What is meant by thermal decomposition?

.....................................................................................................................................

..................................................................................................................................... (2)

(e) Explain, as fully as you can, why cracking is used in the oil industry.

To gain full marks in this question you should write your ideas in good English. Put them into a sensible order and use the correct scientific words.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (3)

(f) The cracking reaction produces a mixture of products. The mixture contains hydrocarbons with different boiling points.

Suggest a method of separating this mixture.

.....................................................................................................................................

..................................................................................................................................... (1)

(Total 9 marks)

Q3. Crude oil is a mixture of many compounds. The diagram below shows some of the processes that take place in a petrochemical plant.

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(a) Name the process which takes place in the COLUMN.

..................................................................................................................................... (1)

(b) Name the type of reactions which take place in:

(i) REACTOR 1 ..............................................................................................

(ii) REACTOR 2 .............................................................................................. (2)

(c) The petroleum gases contain ethane, C2H6 and propane, C3H8.

The structure of a molecule of ethane can be represented as:

ethane

Draw the structure of a molecule of propane in the space below.

propane

(1)

(d) Ethane and propane are said to be saturated hydrocarbons. What does saturated mean when used to describe hydrocarbons?

(1)

(e) Many molecules of ethene join together to form poly(ethene) in REACTOR 2.

Complete the diagram below to show the formation of poly(ethene).

(2)

(Total 7 marks)

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Q4. Most plastic bags are made from poly(ethene).

Poly(ethene) is a polymer made from ethene.

Ethene is made by cracking saturated hydrocarbons from crude oil.

(a) Use words from the box to complete the sentences about cracking.

alkanes alkenes catalyst fuel gas

Cracking involves heating the .......................................... to make a vapour.

The vapour is either passed over a hot ............................................... or mixed

with steam and heated to a very high temperature so that thermal decomposition

reactions happen. (2)

(b) Poly(ethene) molecules are made from ethene molecules by a polymerisation reaction.

Describe what happens in a polymerisation reaction.

........................................................................................................................

........................................................................................................................

........................................................................................................................ (2)

(c) There are millions of plastic bags in use. After use most of these plastic bags are buried in landfill sites. The amount sent to landfill could be reduced if the plastic bags: • could be reused • could be recycled by melting and making into new plastic products • could be burned to release energy

Use the information above and your knowledge and understanding to give the positive and negative environmental impacts of using these methods to reduce the amount of plastic bags sent to landfill.

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................ (6)

(Total 10 marks)

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Q5. The label has been taken from a tube of Humbrol Polystyrene Cement, a glue used in model making.

(a) The solvent used is 1,1,1-trichloroethane. The structural formula of this molecule is:

(i) What do the lines between the atoms represent?

........................................................................................................................... (1)

(ii) State whether 1,1,1-trichloroethane is saturated or unsaturated. Give one reason for your answer.

...........................................................................................................................

...........................................................................................................................

........................................................................................................................... (1)

(iii) 1,1,1-trichloroethane is being replaced in favour of a ‘better’ solvent. Use information on the label to help you to suggest why.

...........................................................................................................................

........................................................................................................................... (1)

(b) Polystyrene is a plastic. Plastics are polymers which are made by the process of polymerisation.

(i) What is meant by polymerisation?

...........................................................................................................................

........................................................................................................................... (2)

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(ii) The table gives information about monomers and the polymers made from them. Complete the table.

(3)

(Total 8 marks)

Q6. Known crude oil reserves are being used up rapidly. Crude oil is used to produce many useful fuels, such as petrol. One way to conserve crude oil reserves would be to increase the production of bio-fuels.

(a) Ethanol can be produced for use as a bio-fuel. Cars can be powered by ethanol or ethanol–petrol mixtures.

Sugar cane can be fermented to give a mixture of water (boiling point 100 °C) and ethanol (boiling point 78 °C).

(i) How can ethanol be separated from water?

..........................................................................................................................

.......................................................................................................................... (1)

(ii) Ethanol, C2H5OH, burns to release heat energy.

Complete the balanced symbol equation by writing in the formulae of the two products.

C2H5OH + 3O2 2......... + 3......... (2)

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(b) The cost of producing a bio-fuel, such as ethanol, by fermentation, is at least three times higher than the production cost of petrol. It costs less to produce ethanol from alkanes. In the production, the vapour of an alkane is passed over a hot catalyst.

Ethene is then converted into ethanol.

(i) What has happened to the hexane to produce ethene?

.......................................................................................................................... (1)

(ii) Complete the structural formula for ethene, C2H4.

C C (1)

(iii) Name the compound that is added to ethene to produce ethanol, C2H5OH.

.......................................................................................................................... (1)

(c) As explained in parts (a) and (b), ethanol can be made using either sugar or alkanes as the starting material.

Evaluate the advantages and disadvantages of using these two starting materials to produce ethanol.

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

.................................................................................................................................... (4)

(Total 10 marks)

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C1.6 Plant oils and their uses Revision Higher

Q1. An advert for crisps claims that they now contain only 30% saturated fat because they are cooked in sunflower oil.

(a) The oil is extracted from sunflower seeds. The diagram shows how this can be done.

Draw a ring around the correct word in each box to complete the sentences.

(i)

evaporating.

The oil is obtained from crushed sunflower seeds by filtering.

pressing.

(1)

(ii)

burn

The oil does not dissolve in water.

melt

(1)

(b) Draw a ring around the correct word in the box to complete the sentence.

Carbon carbon double bonds in sunflower oil can be detected

bromine.

by reacting with iron.

oxygen.

(1)

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(c) Water has a boiling point of 100 °C. Sunflower oil has a boiling point above 232 °C.

Suggest why sunflower oil and not water is used to make crisps from thin slices of potato.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (2)

(Total 5 marks)

Q2. Many plants produce useful oils.

(a) The diagram shows some apparatus used to obtain oil from plant material.

Four parts of the apparatus are labelled, A, B, C and D.

Use the information in the diagram to complete the sentences.

Steam is made in part .

Oil from the plant material is vaporised in part .

Steam and oil vapour are condensed in part . (3)

(b) A student investigated a mixture of a plant oil and water.

(i) A mixture of the plant oil and water was shaken and left to stand for 10 minutes.

Page 40

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

dissolves.

floats.

sinks.

The plant oil separates from the water because it

(1)

(ii) A mixture of the plant oil, water and egg yolk was shaken and left to stand for 10 minutes. The mixture did not separate.

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

a compound.

an emulsion.

a fat.

The plant oil, water and egg yolk make

(1) (Total 5 marks)

Q3. Use the correct words from the box to complete the sentences.

higher hydrogen lower

oxygen saturated unsaturated

(i) Animal and vegetable oils that contain .................................. fats can be hardened. (1)

(ii) When oils are hardened with .................................. gas, a chemical change takes

place, producing margarine which has a .................................. melting point than

the original oil. (2)

(Total 3 marks)

Page 41

Q4. This information was taken from a label on a packet of crisps.

Main ingredients:

Potatoes, vegetable oil, Worcester sauce flavour,

colourings, flavourings, salt.

Nutritional information (per 100 g):

Energy 2040 kJ

Protein 6.5 g

Carbohydrate 55 g

of which sugars 3 g

Fat 27 g

of which saturates 9 g

unsaturates 18 g

Fibre 4.5 g

Sodium 1.2 g

Saturated fats are linked to heart problems. In order to claim that their crisps are healthy, the manufacturer keeps the proportion of saturated fats low.

(i) What type of fat contains double carbon carbon bonds?

..................................................................................................................................... (1)

(ii) The colour of bromine water is orange.

What is seen when bromine water is shaken with:

an unsaturated fat ........................................................................................................

a saturated fat? ............................................................................................................ (2)

(iii) Unsaturated vegetable oils can be hardened to make them useful as spreads. Describe how unsaturated vegetable oils are hardened.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (2)

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Q5. (a) The diagrams show the results of shaking a vegetable oil with the substances indicated.

(i) Give a reason for the result in Flask 1.

..........................................................................................................................

.......................................................................................................................... (1)

(ii) Explain the result in Flask 2.

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (2)

(b) Saturated fats are linked to heart problems. Oils that are unsaturated help to prevent heart disease. A company wants to make a ‘healthy’ soft margarine.

The company tested the same volume of different vegetable oils by shaking each with three drops of iodine solution. The results are shown in the table.

Vegetable oil Time in minutes for the

colour of iodine to ‘disappear’

Olive oil 3.5

Peanut oil 3.0

Soya oil 1.5

Sunflower oil 1.0

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(i) Why does iodine react with the molecules in these oils?

..........................................................................................................................

.......................................................................................................................... (1)

(ii) Use the company results to evaluate which one appears to be the most ‘healthy’ vegetable oil to use in the soft margarine.

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (2)

(c) The ingredients of soft margarine include hydrogenated vegetable oil.

(i) Why is hydrogenated vegetable oil used in soft margarine?

..........................................................................................................................

.......................................................................................................................... (1)

(ii) Describe how vegetable oils are hydrogenated.

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (2)

(Total 9 marks)

Q6. An advert for crisps claimed that they are healthier because they are cooked in sunflower oil.

(a) A student found the following information about four oils that are used to make crisps.

Rapeseed oil Sunflower oil Olive oil Corn oil

Saturated fat (%) 6.6 12.0 14.3 14.4

Polyunsaturated fat (%)

29.3 63.3 8.2 51.3

Melting point (°C) +5 –18 –12 –15

One hypothesis is that oils are thought to be healthier if they are: • low in saturated fat

• high in polyunsaturated fat.

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(i) Use the table to decide which oil should be healthiest. Explain your decision by comparing this oil with other oils from the table that you think are less healthy.

Healthiest oil is .....................................................................................

Explanation ...........................................................................................

...............................................................................................................

............................................................................................................... (2)

(ii) These oils can be hardened by reacting them with hydrogen. A student said that hardening would make sunflower oil healthier. Is this student’s claim correct?

Explain your answer.

...............................................................................................................

...............................................................................................................

............................................................................................................... (2)

(b) A mixture of the olive oil, water and egg yolk was shaken and left to stand. The olive oil and water do not separate.

The diagram shows a simple model of how a stable mixture of olive oil and water is produced by the addition of egg yolk.

Use this simple model to explain how the molecules in the egg yolk are able to produce a stable mixture of olive oil and water.

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................ (3)

(Total 7 marks)

Page 45

Q7. An advert for some crisps claims that they now contain only 30% saturated fat because they are cooked in sunflower oil. The crisp company used bromine water to compare percentage unsaturation of sunflower oil with four other vegetable oils, A, B, C and D.

Oil

Volume of bromine water added until the bromine colour just remains (cm3)

Percentage unsaturation

(%) Test 1 Test 2 Test 3 Average

Sunflower 25.4 28.0 27.0 26.8

A 13.0 14.0 15.0 14.0 35

B 23.2 11.2 24.0 23.6 59

C 19.9 21.1 20.2 20.4 51

D 9.5 8.8 9.3 9.2 23

(i) What is the range of percentage unsaturation for oils A, B, C and D?

Range = ................................................ % (1)

(ii) Describe and explain what happens to the first drops of bromine water that are added to these oils.

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (2)

(iii) The average for oil B is given as 23.6 cm3.

Explain how this average has been calculated.

.....................................................................................................................................

..................................................................................................................................... (1)

(iv) The results did not show that sunflower oil contains 30% saturated fat.

Explain why. (You will need to calculate the percentage unsaturation of sunflower oil.)

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (2)

(Total 6 marks)

Page 46

C1.7 Changes in the Earth and it’s atmosphere Revision Higher

Q1. The diagram represents a section through the Earth showing the layers which are labelled A, B, C and D.

(a) Give the name of:

(i) layer A .............................................................................................................

(ii) layer B ............................................................................................................. (2)

(b) Give one difference between layer C and layer D.

....................................................................................................................................

.................................................................................................................................... (1)

(Total 3 marks)

Q2. A map of the world shows that the outline of South America looks as if it would fit into the west coast of Africa.

• Alfred Wegener in 1920 suggested his idea that the continents had been joined together but then slowly drifted apart.

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• Other scientists in 1920 said that the continents were fixed on solid Earth and had been joined by a land bridge.

Modern South American animals are different from modern African animals.

Most fossils of animals found in South America and Africa are exactly the same.

(a) Consider the information above.

(i) What evidence gave Wegener the idea that the continents of South America and Africa had been joined?

..........................................................................................................................

.......................................................................................................................... (1)

(ii) Suggest two reasons why the other scientists in 1920 thought that Wegener was wrong.

1 .......................................................................................................................

..........................................................................................................................

2 .......................................................................................................................

.......................................................................................................................... (2)

(b) Complete the sentences by writing in the correct words.

Recent evidence has supported Wegener’s idea.

The Earth’s .................................. and the upper part of the mantle are now thought to

be composed of tectonic plates.

Heat released by radioactive processes causes convection currents within the Earth’s

.................................. These convection currents cause the plates to move a few

centimetres per ................................... (3)

(Total 6 marks)

Page 48

Q3. (a) The diagram shows the layered structure of the Earth.

(i) Write in the boxes the name of layer X and the name of layer Y. (2)

(ii) The overall density of the Earth is about 5500 kg/m3. The average density of the rocks in the Earth’s crust is about 2800 kg/m3. What does this suggest about the material that makes up the lower layers of the Earth?

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (2)

(b) In 1915, the scientist Alfred Wegener suggested that Africa and South America had once been joined but had since drifted apart. Evidence for his theory came from the animal fossils found in the two continents. The fossils are almost the same, although animals now living in Africa and South America are different. Other scientists did not agree with Wegener and suggested that a land bridge had once joined the two continents.

Page 49

How could scientists use the idea of a land bridge to explain the evidence put forward by Wegener?

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (2)

(c) Scientists now think that the outer layer of the Earth is cracked into a number of large pieces called tectonic plates. The tectonic plates are moving very slowly. The lines on the diagram show the boundaries between the major tectonic plates.

(i) Explain why there are no major earthquakes in Britain.

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (2)

(ii) What is causing the tectonic plates to move?

..........................................................................................................................

.......................................................................................................................... (1)

(Total 9 marks)

Page 50

Q4. The diagram shows a view of the inside of the Earth.

Adapted from Physics for You (1996) by Keith Johnson, Nelson Thornes

(a) The curved lines marked X show two of the slow currents in the mantle.

(i) What sort of currents are these?

.......................................................................................................................... (1)

(ii) How do these currents occur and what is their energy source?

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

..........................................................................................................................

.......................................................................................................................... (3)

(b) Movements of the plates of the Earth’s crust can result in earthquakes.

Give two other geological results of these movements.

1 ..................................................................................................................................

2 .................................................................................................................................. (2)

(Total 6 marks)

Page 51

Q5. Billions of years ago, the Earth’s early atmosphere was probably like the atmosphere of Venus today.

The table shows a comparison of the atmospheres of the Earth and Venus today.

Percentage composition of atmosphere

Name of gas Earth today Venus today

Nitrogen 78 3.5

Oxygen 21 a trace

Argon 0.97 a trace

Carbon dioxide 0.03 96.5

Average surface temperature 20 ºC 460 ºC

(a) Use the names of gases from the table to complete the sentences.

(i) In the Earth’s atmosphere today, the main gas is .................................................. . (1)

(ii) In the Earth’s atmosphere billions of years ago, the main gas was

............................................................ . (1)

(b) (i) Scientists do not know the accurate composition of the Earth’s early atmosphere. Suggest why.

...........................................................................................................................

........................................................................................................................... (1)

(ii) Use information from the table to answer this question.

Water vapour is present in the atmospheres of the Earth and Venus today. The Earth’s surface is mainly covered by water.

Suggest why there is no water on the surface of Venus.

...........................................................................................................................

........................................................................................................................... (1)

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(c) The diagram shows how carbon dioxide is removed from the Earth’s atmosphere.

Describe what happened to the carbon dioxide in the Earth’s early atmosphere. Use the diagram to help you.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (3)

(Total 7 marks)

Q6. (a) During the first billion years of the Earth’s existence, there were many active volcanoes. The volcanoes released the gases that formed the early atmosphere.

Describe how volcanoes caused the oceans to be formed.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (2)

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(b) The atmosphere on Earth today is very different from the early atmosphere.

The pie chart shows the amounts of different gases in the air today. Choose gases from the box to label the pie chart.

argon carbon dioxide hydrogen nitrogen oxygen

(2)

(Total 4 marks)

Q7. For 200 million years the proportions of the different gases in the atmosphere have been much the same as today. Over the past 150 years the amount of carbon dioxide in the atmosphere has increased from 0.03% to 0.04%.

(a) Describe how carbon dioxide is released into the atmosphere:

(i) by human and industrial activity;

...........................................................................................................................

...........................................................................................................................

...........................................................................................................................

........................................................................................................................... (2)

(ii) from carbonate rocks by geological activity.

...........................................................................................................................

...........................................................................................................................

...........................................................................................................................

........................................................................................................................... (2)

Page 54

(b) Explain how the seas and oceans can decrease the amount of carbon dioxide in the atmosphere.

.....................................................................................................................................

.....................................................................................................................................

.....................................................................................................................................

..................................................................................................................................... (3)

(c) (i) Give one reason why the amount of carbon dioxide in the atmosphere is increasing gradually.

...........................................................................................................................

........................................................................................................................... (1)

(ii) Give one effect that increasing levels of carbon dioxide in the atmosphere may have on the environment.

........................................................................................................................... (1)

(Total 9 marks)

Q8. Air is a mixture of gases and contains various pollutants. The gases are useful and can be separated by fractional distillation of liquid air. The table gives information about some of the gases in air.

Name of gas Formula Melting point in °C Boiling point in °C

Helium He –272.2 –269.0

Oxygen O2 –219.0 –183.0

Nitrogen N2 –210.0 –195.9

Argon Ar –189.0 –185.9

Carbon dioxide CO2 –78.5 –78.5

Water vapour H2O 0.0 100.0

To separate these gases:

• the air is filtered • water is removed first • carbon dioxide is then removed by absorption • the gases remaining are compressed and cooled to –200 °C.

Page 55

(a) The air is filtered before the gases are separated.

Suggest why.

........................................................................................................................

........................................................................................................................ (1)

(b) Water vapour and carbon dioxide are removed before the gases are compressed and cooled.

Use the information in the table to suggest why.

........................................................................................................................

........................................................................................................................

........................................................................................................................

........................................................................................................................ (2)

(c) After the water and carbon dioxide have been removed, which gas stays liquid over the greatest temperature range?

........................................................................................................................ (1)

(d) After the water and carbon dioxide have been removed, the four gases that are left are compressed and cooled to –200 °C.

(i) Which gas does not liquefy?

............................................................................................................... (1)

(ii) The three liquefied gases are then allowed to warm up.

Give the order in which the three liquefied gases would vaporise.

1st ...................................................

2nd ..................................................

3rd ................................................... (1)

(Total 6 marks)

Page 56

C1.1 Answers

M1.

[4]

M2. (a) A – electron 1

B – nucleus 1

C – proton 1

D – neutron 1

(b) Group 1 / alkali metals 1

has one electron in outer shell

accept 3 protons / 3 electrons / atomic number 3 therefore lithium (so Group 1 / alkali metals)

1

(c) lithium

accept Li 1

[7]

M3. (a) a substance which contains one type of atom or a substance that cannot be broken down into anything simpler

for 1 mark 1

(b) more than one element/more than one type of atom combined/join together/bonded

for 1 mark each 2

[3]

Page 57

M4. (a) (i) both have one / 1 electron in the outer energy level / shell

allow both react in a similar way 1

(ii) eleven / 11 1

(iii) twelve / 12 1

(iv) (2x)

max 1 if candidate changes the number of electrons in the first energy level / shell

8x (in second energy level / shell) 1

1x (in outer energy level / shell) 1

(b) two sodium atoms (react) 1

two (bonded) chlorine atoms (react)

allow one chlorine molecule (reacts) 1

two sodium ions and two chloride ions (are produced)

allow two molecules of sodium chloride (are produced) or two sodium chloride particles (are produced)

1

[8]

M5. (a) (i)

or 1

allow any arrangement of electrons on the shells

accept o, x, - or e as representing electrons

(ii) nucleus

accept nucleus (protons plus neutrons)

do not accept protons plus neutrons on its own

allow nuclei / nucles / neucleus / phonetic spelling

do not accept neutron 1

(b) it has 2 more neutrons or converse

accept ‘it has more neutrons’ or ‘different number of neutrons’ for 1 mark

‘2 more protons / electrons + correct number of neutrons’ =

Page 58

max 1 mark

or

O-16 has 8 neutrons (1 mark)(*)

O-18 has 10 neutrons (1 mark)(*)

(*)if incorrectly calculated but shows more neutrons in 0-18 allow for 1 mark

accept it has more particles

or

it has 2 more particles for 1 mark 2

[4]

M6. (i) two circles together and shaded i.e. one molecule

1

(ii) made up of one type of atom

accept made up of atoms which contain the same number of protons

accept a substance that cannot be split up into simpler substances by chemical means

do not accept they are in the Periodic Table 1

(iii) no marks can be awarded if there is any reference to mixture or mix

made up of two or more types of atoms

accept made up of two or more elements 1

(chemically) bonded

accept joined or combined for bonded

do not accept fused 1

[4]

M7. (a) (i) element 1

(ii) compound 1

(b) an / one electron from the sodium atom 1

is lost / transferred to form a sodium ion 1

(c) (i) 8 electrons drawn on outer energy level / shell 1

(ii) because oppositely charged ions attract each other

or

because chloride ions are negative and sodium ions are positive 1

[6]

Page 59

M8. (a) C3H8

capital letters for symbols numbers must be halfway or lower down the element symbol

allow H8C3

do not allow 3:8 or C3 and H8

1

(b) (i) electron 1

(ii) covalent 1

(c) low and small

both for 1 mark 1

[4]

M9. (a)

both correct in each row

electron ...– (1)

allow negative 1

1 .......... 0

allow neutral or none 1

proton .....+ (1)

allow positive 1

(b) (i) protons...electrons

both correct in correct order 1

(ii) protons....neutrons

both correct in either order 1

(c) (i) sodium fluoride

do not credit sodium fluorine 1

NaF

must be correct in every detail

do not credit NAF and the like 1

(ii) ionic

accept ion (bonding)

do not credit ironic or iron (bonding) 1

(iii) electron transferred from sodium to fluorine

Page 60

accept electron transferred from metal to non-metal

either positive sodium ion and negative fluoride ion

or correctly identified by the symbols Na+ and F- accept ‘positive sodium ion and negative fluorine ion’

1

or attracted because have opposite charge(s)

or (atoms/ions) form an (ionic) lattice or (atoms/ions) form a crystal

e.g.

or both marks may be gained by a suitable dot and cross diagram 1

[10]

Page 61

C1.2 Answers

M1. (a) causes dust pollution 1

increases traffic 1

(b) (i) decomposition 1

(ii) 44(g) 1

(c) (calcium) hydroxide 1

(calcium) carbonate 1

substances must be in the order shown [6]

M2. (a) (i) 1 1

3 1

(ii) nucleus 1

electron 1

(b) (i) methane / CH4

accept natural gas

ignore air

do not allow other gases 1

(ii) carbon dioxide 1

(c) (i) any two from:

• medical risks

• asthma

• cancer

• dirt

• causes global warming / global dimming / greenhouse effect / acid rain

ignore death

accept effect on health

accept difficulty breathing/ lung disease

allow smoke particles

allow harmful for the environment 2

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(ii) any two from:

• have a test done / scientific evidence

• independent (evidence)

• comparison of smoke particles / when different fuels used

• medical evidence or more / less asthma attacks or cancer or dirt on cars

2

[10]

M3. (a) (i) 3 / three 1

(ii) 5 / five 1

(b) any one from:

• less / no transport

accept less / no distance

• less / no (fossil) fuel used

ignore references to carbon dioxide / carbon emissions 1

(c) (i) carbon dioxide / CO2

for a correct emission 1

(causes) global warming / climate change / greenhouse gas

explanation must be correct for named emission

ignore ozone layer

or

(cement) particles / smoke (1)

(causes) asthma / dust / (global) dimming (1)

accept breathing problems

or

sulfur dioxide / SO2 / nitrogen oxides / NOx (1)

(causes) acid rain (1)

do not accept nitrogen or water vapour for emissions

do not accept no named emission 1

(ii) absorb / trap / capture / filter / pass through water / scrub / electrostatic attraction

ignore condense / off setting / different fuel 1

[6]

Page 63

M4. (a) calcium carbonate

not formula 1

(b) calcium carbonate → calcium oxide

not common names allow correct formulae

1

+ carbon dioxide 1

(c) calcium hydroxide

not formula 1

(d) CaO + H2O → Ca(OH)2

allow if doubled

all formulae correct, no extra ones 1

balanced 1

(e) filtration allow centrifugation

not decanting not evaporation, crystallisation

1

(f) electrolysis stated or implied

molten MgO / magnesium oxide is ionic / Mg2+ goes to cathode

not just heated 1

or add sodium / K / Ca / Li / a more reactive metal 1

displaces Mg / reduces Mg

give no marks if reference made to reduction by C or H 1

[9]

Page 64

M5. (a) limestone clay

both for 1 mark 1

(b) water sand crushed rock

for 1 mark each 1

[4]

M6. (a) (i) calcium oxide / quicklime

allow calcium monoxide

do not accept calcium dioxide

ignore chemical formulae 1

(ii) any three from:

• carbon dioxide / CO2

• (carbon dioxide) reacts (with the calcium hydroxide / slaked lime / plaster)

allow reaction 3 identified do not allow incorrect reaction ignore mixes, unless they state the correct product

• limestone / calcium carbonate / CaCO3 forms

allow marble / chalk

• water is lost / evaporates

it = plaster

allow moisture ignore dries

3

(b) (i) as the amount / volume of sand decreases the strength of the mortar increases

accept as sand decreases the mortar is stronger / harder to crack

allow as sand decreases the mortar increases

allow converse

ignore references to height of metal ball 1

(ii) any two from:

Page 65

• 400 / 5th result is anomalous

accept two results (36 and 37 / 400 and 500 / 4th and 5th) are almost the same accept result at 400 should be 42

• the interval between the others is similar or the interval is about 6/7

allow the other results fit a pattern / are on a straight line

• he has only one set of results

allow he has only done it once

ignore reliable 2

[7]

M7. (a) (i) clay

for one mark

(ii) calcium oxide / quicklime / CaO

for one mark

(iii) sensible answers such as cost of fuel etc. / accept a wide range of appropriate answers

for one mark 3

(b) sand gravel (owtte) e.g. crushed rock water

any two for 1 mark each 2

[5]

M8. (i) (hot air) gives faster reaction makes coal burn faster (provides air / oxygen to help to) allow the coal to burn / helps combustion flushes out the waste / gases / carbon dioxide

any one for 1 mark 1

(ii) decomposition of limestone yields carbon dioxide (owtte) the combustion / burning of coal produces carbon dioxide (owtte)

each for 1 mark 2

[3]

Page 66

C1.3 Metals and their uses Higher Answers

M1. (a) atoms

1

(b) mixture 1

metal 1

structure 1

smart 1

(c) (i) any two from:

• saves raw materials / iron ore

• saves energy / fuels

accept cheaper / saves money

• make new / useful items

• make money / it is economic

• reduces pollution

allow less harmful for the environment

• decreases cost of steel cans

• reduces carbon dioxide emissions

• decreases waste materials / use of landfill 2

(ii) any one from:

• provide information / education of the need to recycle

• legislate against / charge for waste

• reward / pay people to recycle

accept fine people for not recycling

• put labels on the cans

• provide recycling bags / bins / areas 1

[8]

M2. (a) (i) any one from:

Page 67

• iron ore is a limited resource / non-renewable

• iron is in high demand

• provide jobs

• economic advantage 1

(ii) any two from:

• would damage (wildlife) habitats / countryside / greenfield sites

• extra traffic

• visual (pollution) / eyesore

• noise (pollution) / sound (pollution)

• dust (pollution)

• river (pollution)

• carbon dioxide (from traffic) / adds to greenhouse effect / global warming

• damage roads / buildings by vibrations / shockwaves 2

(b) (i) carbon monoxide / carbon

accept formulae CO / C 1

(ii) atoms

accept (particles) are all the same (size) / type for one mark

1

are all the same (size) / type 1

(iii) any two from:

• impurities / carbon / different (sized) atoms or elements or metals

• changes the structure / disrupts the pattern or layers

• prevents layers sliding over each other

• it is an alloy 2

[8]

M3. (a) good (electrical) conductor

allow low reactivity / resistance to corrosion

do not accept heat conductor 1

Page 68

(b) a mixture of metals

accept contains more than one type of metal 1

(c) (i) any one from:

• eyesore

• destruction of habitats

• pollution of water

• dust pollution

• noise

• traffic pollution 1

(ii) acid rain

allow sulfur dioxide is a pollutant

1

(d) (i) running out of copper (ores) 1

(ii) any two from:

• any specific example of using less copper

• reuse / recycle

allow do not throw copper / brass away

• use low-grade copper ores

• use other metals / materials in place of copper 2

[7]

M4. (a) (an alloy) that can return to its original shape (after being deformed / bent / twisted)

accept (on heating / cooling) it returns to its shape

1

(b) any two from:

• brass / it is a mixture

accept brass / it is not pure

• zinc changes structure / disrupts patterns or layers

Page 69

• copper metal atoms / layers able to slide over each other

accept zinc prevents atoms / layers sliding over each other 2

(c) (i) oxygen / O2 / O 1

(ii) lead remains (in furnace) because of its high boiling point 1

zinc boils / evaporates (out of furnace) because of its low boiling point 1 if neither mark awarded then allow 1 mark for different boiling points

ignore references to melting points 1

[6]

M5. (a) (very) small percentage / amount (in the Earth’s crust)

any indication that there is a small amount, eg not much (left) accept rare (elements) / rarer accept not commonly found ignore cannot find easily ignore hard to extract

1

(b) (i) oxygen / O / O

do not accept O

1

(ii) any one from:

• potassium / K • sodium / Na • calcium / Ca • magnesium / Mg

symbols must be correct write name and incorrect symbol, ignore symbol

1

(c) (i) heating (with) or hot air blown into furnace

accept high temperatures or (very) hot 1

carbon / carbon monoxide / coke / coking coal

do not accept coal / charcoal accept balanced equation only

orcarbon reacts with O2 or carbon / coke burning (1)

accept balanced equation only CO / CO2

CO reacts with the ore (1)

for naming the reducing agent 1

(ii) cost of melting ore / electricity makes aluminium expensive (owtte)

Page 70

or (large amount of) electricity used or because you have to use electrolysis or aluminium is higher in the reactivity series or aluminium is harder to reduce or unable to reduce with carbon or the cost of purifying the bauxite

do not accept harder to extract / produce more energy is not enough

1

[6]

M6. (i) idea that:

carbon is above lead in the reactivity series } NOT

for 1 mark

carbon is below aluminium in the reactivity series } OXIDE

for 1 mark

carbon can remove oxygen from/reduce lead oxide or cannot remove oxygen from aluminium oxide not aluminium more reactive than lead

for 1 mark

OR similar ideas in comparing bond strengths 3

(ii) (carbon + lead oxide) →*lead + *carbon dioxide

each for 1 mark

accept correct formulae CO2 and CO NOT carbon oxide

2

[5]

M7. (a) any two points one mark each

accept comparison between aluminium and iron

aluminium has:

• a low density

accept lighter or fewer pylons

• a good conductor of electricity

• does not corrode or rust

do not accept does not react with air

do not accept last longer 2

OR

• iron has:

• high density

• is a less good conductor (of electricity)

• rusts or reacts with air

Page 71

(b) any 5 from:

• employment of people or cost of employment

• depletion or use of resources

do not accept depletion here

• cost of energy resources

• cost of machines or buildings

• pollution by noise from traffic or quarrying

• air pollution by dust or traffic fumes

• danger of traffic on roads

• damage to landscape (eyesore)

• damage to habitats of wildlife

• lowers the value of houses nearby

• subsidence or vibration can affect roads or houses

• providing raw materials

do not accept danger or falling in 5

[7]

M8. (a) unreactive / near bottom of reactivity series

1

(b) carbon more reactive / higher up reactivity series 1

(c) very reactive / near top of reactivity series 1

cannot use displacement methods / can only be extracted by electrolysis / had to wait discovery of electricity

1

[4]

Page 72

C1.4 Answers

M1. (i) carbon and hydrogen only or compound of

for 1 mark each 2

(ii) single bonds only or no double bonds etc or contains maximum number of hydrogen atoms

for 1 mark 1

(iii) molecules of similar chain length similar boiling points limited range of boiling points etc

any 1 for 1 mark 1

[4]

M2. (i) C8H18

for one mark 1

(ii) mixture

for one mark 1

(iii) fractions molecules atoms evaporated condensed

in this order for 1 mark each 5

[7]

M3. B will have higher melting point higher boiling point be less volatile be more viscous (allow less flammable)

any two for 1 mark each [2]

M4. (a) the more C atoms the higher the b.pt./temperature Allow just higher. Not answer based on melting point

for 1 mark 1

(b) (fractional) distillation/fractionation

for 1 mark 1

Page 73

(c)

must include H atoms and lines not CH3 – CH3

for 1 mark 1

[3]

M5. (a) decane has the largest molecules 1

methane and butane are gases at 20 °C 1

(b) (i) water 1

(ii) carbon dioxide 1

(c) sulfur dioxide is produced when sulfur burns 1

therefore sulfur must be removed from these fuels because sulfur dioxide causes acid rain

1

[6]

M6. (a) (i) X and Y

both needed 1

(ii) Z 1

(iii) X 1

(b) unsaturated / alkenes / those with double (C = C) bonds 1

[4]

Page 74

M7. (a) each bar correct height (2 bars) to less than ½ square

1 mark for each

both bars correctly labelled (in relation to size of bars)

for 1 mark 3

(b) less

gains 1 mark

but a lot less / much less / 18 times less or more if referring to coal

gains 2 marks 2

(c) (i) carbon sulphur

for 1 mark each 2

(ii) ideas that

• at high temperatures, (produced when fuels burn)

• nitrogen and oxygen from atmosphere combine / react

for 1 mark each 2

M8. (a) (i)

do not credit CH3CH3

1

(ii)

do not credit C2H4

1

(iii) burn or react with oxygen or combustion or oxidation

accept react with chlorine 1

(iv) bubble each gas through (test tube containing) bromine water

accept add bromine (water to gas collected) or burn 1

ethene decolourises it or turns the brown colourless

do not accept makes it go clear 1

ethane does not affect it or leaves it brown 1

Page 75

(b) both the correct name and use are required for the mark poly (ethene) or polythene; any soft or pliable plastic article or any suitable harder plastic item

accept polyethene or polyethylene 1

M9. (a) (i) acid rain

accept consequences of acid rain

allow asthma / bronchitis

ignore toxic gas 1

(ii) global dimming

accept dimming alone 1

(b) (i) sustainable:

maximum two from:

• crops (that produce oil) can be grown in most places owtte

• renewable

• use less fossil fuels / diesel

• use (refined) waste oils

low pollution:

maximum two from:

ignore references to CO2 here

• most emissions are lower or any two named emissions from CO / SO2 / PM10 are lower

• much / lot less SO2 emissions (than the others) owtte

• accept spillages / waste is biodegradable

• less new CO2 or (more) carbon neutral 3

(ii) plants / photosynthesis use carbon (dioxide) from the air* 1

it / biodiesel releases carbon (dioxide) from plants / crops / photosynthesis*

(*) allow 1 mark for biodiesel is (more) carbon neutral 1

(fossil) diesel releases ‘locked up’ / new carbon (dioxide) / doesn’t absorb CO2 / absorbed it millions of years ago

1

[8]

Page 76

C1.5 Answers

M1. (a) (i) the greater the number (of carbon atoms), the higher its boiling point

do not accept hydrocarbons for carbon atoms

allow converse

allow melting point 1

(ii) accept answers in the range 344 to 350 1

(iii) 216 1

(b) (i) EITHER

shortage of petrol or demand for petrol is higher than supply

diesel is in excess or supply of diesel is higher than demand 1

OR

petrol low supply and diesel high supply (1)

petrol high demand and diesel low demand (1)

petrol / diesel not specified = max 1 1

(ii) any one from:

• use diesel to make petrol

accept crack diesel or description of cracking

• make diesel cheap(er) (than petrol) or make petrol more expensive

accept lobby the government to reduce the tax on diesel / increase tax on petrol

• mix ethanol with petrol

ignore biodiesel 1

[6]

Page 77

M2. (a) catalyst or speeds up the reaction (owtte)

accept lowers activation energy not just helps reaction to take place ignore increased surface area

1

(b) C8H18

allow H18C8

must be upper case do not accept powers

1

(c) B because it is a gas or because it has small molecules or because they are small

position and reason for mark allow it has a lower / very low boiling point than A ignore references to solubility accept does not condense do not accept light molecules or bubbles into B do not accept it is small

1

(d) breakdown of a substance (owtte)

do not accept decompose unqualified 1

by the action of heat (owtte) 1

(e) Quality of written communication

if the written communication makes sense and it is in context then award Q mark

Q Q 1

large to small molecules or scientific word that implies smaller, e.g. alkene / ethane / petrol

any name or formula of alkane / alkene smaller than decane 1

either advantages of smaller molecules or disadvantages of larger molecules e.g. hydrocarbons with large molecules are limited in their usefulness

or converse for smaller molecules 1

large hydrocarbon molecules do not ignite easily / do not flow easily / are not very volatile

or converse for smaller molecules

more large hydrocarbon molecules are produced than are needed

Page 78

or converse for smaller molecules

smaller molecules are useful as fuels

alkenes / products can be used to make polymers

(f) (fractional) distillation

accept fractionation accept good description do not accept just diagram

1

[9]

M3. (a) (fractional) distillation/fractionation

for 1 mark 1

(b) (i) cracking/decomposition

for 1 mark 1

(ii) polymerisation/addition reaction

for 1 mark 1

(c)

(Must have H atoms)

for 1 mark 1

(d) contains only/all single bonds no double bonds contains maximum number of H atoms carbon atoms bonded to 4 other atoms (not 4 H atoms) will not undergo addition reactions

any 1 for 1 mark 1

Page 79

(e) (n must be on (right))

= 2 marks

(n on left = 1 mark)

= 2 marks

= 1 mark

= 1 mark

(Double bond loses both marks)

= 0 marks

OR

= 2 marks

Page 80

(for both a minimum of 4 carbon atoms)

= 1 mark

= 2 marks

= 1 mark

= 1 mark 2

[7]

M4. (a) alkanes 1

catalyst 1

substances must be in the order shown

(b) many (ethenes/monomers) 1

bond/join together 1

allow ethenes / monomers bond / join together to form very large molecules for 2 marks

(c) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response.

No relevant content. 0 marks

Page 81

There is a brief description of a positive and a negative environmental impact involved with one or more methods used to reduce the amount of plastic bags sent to landfill.

Level 1 (1–2 marks)

There is some description of both positive and negative environmental impacts involved with at least 2 methods used to reduce the amount of plastic bags sent to landfill.

Level 2 (3–4 marks)

There is a clear, balanced and detailed description of both a positive and a negative environmental impact of using each of the 3 methods used to reduce the amount of plastic bags sent to landfill.

Level 3 (5–6 marks)

examples of the chemistry points made in the response

reuse: reuse means less bags used so:

positive environmental impact

• saves raw materials / crude oil

• saves energy

• cuts down on CO2 emissions

• less global warming

negative environmental impact

• could cause litter

• could still be sent to landfill

recycle: bags bought can be recycled so:

positive environmental impact

• used to make new plastic bags / objects

• saves raw materials / crude oil

• saves energy compared to producing plastic bags from crude oil

• cuts down on CO2 emissions

• less global warming

negative environmental impact

Page 82

• collection point sites cause an eyesore / litter problem

• transportation to recycling plant releases carbon dioxide / causes global warming

burn: bags can be burned so:

positive environmental impact

• could provide energy for heating buildings

• could provide energy for generating electricity

negative environmental impact

• increases CO2 emissions

• increases global warming

• could release toxic gases

does not conserve raw materials / crude oil [10]

M5.(a) (i) bonds / pair of electrons / shared electrons

for one mark 1

(ii) saturated since it has single bonds / no double bonds / no multiple bonds / maximum number of atoms attached

for one mark 1

(iii) sensible answer (e.g. it is harmful) or better solvent could be used on expanded polystyrene or foam

for one mark 1

(b) (i) simply writing monomers form / react to form polymers gains no mark

Page 83

monomers join / bond / combine / link to form polymers = 1 mark the mark is for the idea of joining to gain the second mark the idea of the relative size of monomer and polymer is required small molecules join to form a polymer (2 marks) many monomers join to form a polymer (2 marks) monomers join to form a large molecule / long chain (2 marks) many molecules join together (2 marks)

for 1 mark each 2

(ii) polyethene / poly(ethene) / polythene

don’t worry too much about the exact positioning of the C6H5 at the end of the bond

placement of linking bonds inside / outside brackets is not important must have n

for 1 mark each [8]

M6. (a) (i) by (fractional) distillation

accept a description of the distillation process (heat and how separation works) eg heat and condense accept boil / vapourise etc for heat

or

fractionation 1

(ii) CO2

note the order of these products must be correct 1

H2O

Page 84

wrong way round = 1 mark 1

(b) (i) (hexane) has been broken down (into smaller hydrocarbons / molecules) 1

accept (thermal) decomposition / cracked / split / broken up owtte

(ii) H H │ │ C = C │ │ H H

accept CH2 = CH2

1

(iii) water / hydrogen oxide / steam

accept H2O 1

(c) candidates must include both sugar cane and crude oil in their evaluation and both an advantage and a disadvantage to gain full marks. if they do not then the maximum mark is three

any four from:

advantages of using sugar

• country has no wealth to buy (large quantities of) crude oil

not ‘expensive’ alone

• country has limited technological development

or

underdeveloped / third world country

• able / suitable climate to grow sugar cane

• enough land to grow sugar cane / land cannot be used to grow food / deforestation

• sugar is a renewable source

or

crude oil is a non-renewable resource / finite resource / limited resources

• CO2 / carbon neutral

advantages of using alkanes:

• economic costs are low

• continuous process

• country has large oil resources

Page 85

• country has oil refineries / cracking plants

• very pure product

• faster process 4

[10]

Page 86

C1.6 Answers

M1. (a) (i) pressing 1

(ii) dissolve 1

(b) bromine 1

(c) temperature needs to be high / above 100 °C

allow melting point 1

or (sunflower oil has a) high(er) boiling point

or boiling point of water is not high enough

any one from:

• remove water / make potato crisp(er)

accept water makes potato soft / soggy

• adds / gives flavour 1

[5]

M2. (a) D 1

C 1

A 1

letters must be in the order shown

(b) (i) floats 1

(ii) an emulsion 1

[5]

Page 87

M3. (i) unsaturated 1

(ii) hydrogen 1

higher 1

[3]

M4. (i) (poly)unsaturated

accept monounsaturated 1

(ii) (turns) colourless or colour disappears / decolourises

do not accept clear 1

stays the same colour / orange / no change

allow yellow-orange / orange-brown / red-orange 1

(iii) (react) with hydrogen / H2 / hydrogenation 1

any one from:

• heated / 60 °C

• catalyst / nickel 1

[5]

M5. (a) (i) water and oil do not mix / are immiscible

ignore density 1

or

don’t dissolve each other

ignore emulsifier alone 1

(ii) any two from:

• emulsifier

• forms an emulsion

accept description of an emulsion

• holds the two components together

accept stops them separating / they mix

allow bonds / binds for holds

• by lowering the surface tension

accept a description of how an emulsifier works for two marks eg ‘tadpole’ diagram or dispersal of oil drops

2

Page 88

(b) (i) (because they contain) a double (carbon carbon) bond

accept unsaturated

ignore poly or mono 1

(ii) results suggest sunflower oil is best

or

‘the one that took the least time’ 1

because (sunflower oil) has the highest amount of unsaturation / most double bonds / least saturated

ignore uses up I2 most quickly

second mark is dependent on first 1

(c) (i) any one from:

• have a higher melting point than (vegetable) oil

• are solid at (room temperature) / hardened / harder

accept useful as spreads or doesn’t soak into bread

ignore hard / soft(er) 1

(ii) any two from:

• hydrogen added

do not accept ‘water’

• to carbon carbon double bond / to saturate

• (nickel) catalyst / temperature 60 – 150 °C

wrong catalyst doesn’t get this mark

ignore high / warm temperature 2

[9]

M6. (a) (i) (healthiest oil is) sunflower (oil) or rapeseed (oil)

sunflower (oil) is healthiest because it has less saturated fat than both olive (oil) and corn (oil)

or

rapeseed (oil) is healthiest because it has the lowest value of saturated fat compared with the other oils

1

sunflower (oil) is healthiest because it has the highest value of polyunsaturated fat compared with all the other oils

Page 89

or

rapeseed (oil) is healthiest because it has more polyunsaturated fat than both olive (oil) and corn (oil)

1

no mark for the choice of oil

accept the use of values from the table for these comparisons

(ii) no, because hydrogen adds to the unsaturated fat or no, because hydrogen reduces the number of carbon–carbon double bonds

accept no because reacting with hydrogen increases number of single bonds

1

therefore there will be less polyunsaturated fat

accept therefore there will be more saturated fat 1

(b) molecules in egg yolk act as emulsifiers

accept lecithin molecules act as emulsifiers 1

because molecules in egg yolk have a ‘head’ which dissolves in / attracted to water

accept because molecules in egg yolk are hydrophilic 1

because molecules in egg yolk have a ‘tail’ which dissolves in / attracted to oil

accept because molecules in egg yolk are hydrophobic 1

[7]

M7. (i) 23 to 59

accept 36 1

(ii) decolourise or (orange to) colourless

ignore discolours / fades

do not allow oil decolourises 1

(because bromine reacts with the) (carbon) double bond

ignore alkenes or reference to unsaturation 1

(iii) any one from:

• an anomalous result (11.2) / Test 2

accept (= 23.6)

Page 90

• 11.2 / Test 2 is ignored when averaging

accept average of tests 1 and 3 1

(iv) unsaturation 67%

average was less than it should be / only 26.8 cm3

1

(this means there is) 33% saturated fat

it should have been 28.0 cm3 to give a percentage of 70% 1

[6]

C1.7 Answers

M1. (a) Layer A = crust / tectonic plates / (not named type of rock) Layer B = mantle / magma

each for 1 mark 2

(b) Layer C is liquid / molten (accept mostly liquid) but layer D is solid Layer D is more dense than layer C. / accept they have different densities Layer D is hotter than layer C. / accept they have different temperatures (Do not accept hardness / viscosity)

any one for 1 mark 1

[3]

M2. (a) (i) old animals / fossils / rocks match (when the continents are put together)

or (continents) fit together

ignore ‘they are the same shape’ 1

(ii) any two from:

• continents / plates cannot move (thousands of kilometres)

accept the continents / plates are attached to the Earth or continents / plates cannot drift / float

• modern / new animals are different

• a land bridge (could explain the matching fossils / rocks)

ignore ‘no evidence’ ‘no proof’ ‘no reputation’ 2

(b) crust

allow lithosphere 1

Page 91

mantle 1

year 1

[6]

M3. (a) (i) X – mantle 1

Y – inner core

do not accept solid core 1

(ii) different to the crust or contains a lot of (heavy) metals

accept iron and nickel for metals 1

higher (average) density or denser

density higher than 5500 (kg/m3) gets 2 marks 1

(b) animals were able to move from one continent to the other 1

(when bridge broke) animals evolved differently accept animals adapted differently

1

(c) (i) earthquakes occur at the boundary between plates or earthquakes occur where plates push against each other

1

there are no plate boundaries running through Britain 1

(ii) convection currents (in the mantle) or heat released by (natural) radioactive processes

accept Britain is not near the edge of a plate 1

[9]

M4. (a) (i) convection (currents)

Page 92

accept (currents) which move the plates 1

(ii) less dense (molten) rock / magma rises / moves up

or more dense (molten) rock / magma falls / moves down 1

heat (is transferred / conducted) to the mantle / crust

(resulting from natural) radioactive processes (in the core) 1

or radioactivity

accept radiation provided there is no

contradiction as in, for example, radiation from the Sun

or fission

do not credit fusion 1

(b) any two from

(formation of fold) mountains

or deformation(s)

hot springs

do not credit just springs

(oceanic) ridges

(oceanic) trench(es)

rift(s)

seismic waves

subduction

or recycling of rocks

tsunami(s)

do not credit tidal waves

volcano(es)

or volcanic activity / sill(s) dyke(s) lava flow(s) 2

[6]

M5. (a) (i) nitrogen / N2

1

(ii) carbon dioxide / CO2

1

(b) (i) humans / scientists had not evolved

Page 93

accept it was billions / millions of years ago

allow too long ago 1

(ii) temperature is above 100°C or any water would evaporate / boil

accept Venus is too hot 1

(c) any three from:

• used by plants

• used for photosynthesis

accept plants take in carbon dioxide and give out oxygen for the first two bullet points ie 2 marks

• dissolves in oceans / seas

allow absorbs into oceans / seas

• used to form the shells / skeletons of marine organisms

• locked up as limestone / carbonates

• locked up as fossil fuels / oil / coal 3

[7]

M6. (a) (i) water vapour given out from volcano

accept steam not hydrogen and oxygen combining to form water

1

condensed

accept rain / clouds formed just ‘cools’ is insufficient 1

(b) nitrogen (left) N

do not accept N 1

oxygen (right) O

do not accept O 1

[4]

M7. (a) (i) burning / breathing / respiration / fuels / food

for 1 mark each 2

(ii) 1. rock is heated / subducted (owtte) / close to magma / melted

Page 94

1. rock is decomposed / carbon dioxide released through volcanoes

for 1 mark each 2

(b) carbon dioxide reacts / dissolves in sea-water / dissolves in rain water insoluble carbonates / calcium carbonate are / is formed carbon dioxide turned into shells / coral / limestone / chalk / sediments also soluble hydrogencarbonates (calcium / magnesium) are formed photosynthesis by plants

any three for 1 mark each 3

(c) (i) sea unable to absorb all the extra carbon dioxide being produced more trees being cut down / deforestation increased burning of fuels / more cars / more industry (not more people)

any one for 1 mark 1

(ii) global warming / greenhouse effect or effects such as melting ice caps / rising sea levels / climatic change / more deserts (not changes to ozone layer)

for one mark 1

[9]

M8. (a) to remove solid / dust particles 1

(b) because at –200 °C both (water and carbon dioxide) are solids 1

this would therefore block pipes / equipment 1

(c) oxygen 1

(d) (i) helium 1

(ii) nitrogen > argon > oxygen 1

[6]