Name: C10 Using Resources. Class: 35 Questions. Date: Time: Marks: Comments: Brookvale Groby Learning Trust

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1 C0 Using Resources 35 Questions Name: Class: Date: Time: Marks: Comments: Page of 0

2 Copper can be produced from copper(ii) sulfate solution by two different methods. Method Electrolysis (a) To produce copper by electrolysis a student has inert electrodes, a d.c. power supply, a switch and electrical wires for the external circuit. Draw and label the apparatus set up to produce copper from copper(ii) sulfate solution by electrolysis. (2) (b) Suggest why the colour of the copper(ii) sulfate solution fades during the electrolysis. (3) (c) Explain how copper is produced from copper(ii) sulfate solution by electrolysis. (4) Page 2 of 0

3 Method 2 Displacement (d) The chemical equation for the displacement of copper using iron is: CuSO 4 + Fe Cu + FeSO 4 Calculate the minimum mass of iron needed to displace all of the copper from 50 cm 3 of copper(ii) sulfate solution. The concentration of the copper(ii) sulfate solution is 80 g CuSO 4 per dm 3. Relative atomic masses (A r ): O = 6; S = 32; Fe = 56; Cu = 63.5 Give your answer to 2 significant figures. Mass of iron = g (4) (Total 3 marks) Page 3 of 0

4 2 The apparatus in the figure below is used to separate a mixture of liquids in a fuel. (a) What is apparatus W on above the figure above? Tick one box. Beaker Boiling Tube Flask Jug () Page 4 of 0

5 (b) What is the name of this method of separation? Tick one box. Crystallisation Electrolysis Filtration Distillation () (c) Name the changes of state taking place at A and B in the figure above. Use words from the box. boiling condensing freezing melting Change of state at A: Change of state at B: (2) Page 5 of 0

6 (d) Table shows the boiling points of the hydrocarbons in the fuel. Table Hydrocarbon Boiling point in C Pentane 36 Hexane 69 Heptane 98 Octane 25 Which hydrocarbon will be the last to collect in the beaker? Tick one box. Pentane Hexane Heptane Octane () Page 6 of 0

7 (e) The fuel is a mixture of liquids that has been designed as a useful product. What name is given to this type of mixture? Tick one box. Catalyst Formulation Polymer Solvent () (f) Describe how this fuel is different from crude oil. (2) Page 7 of 0

8 (g) A student measured the melting point of a solid hydrocarbon four times. The student s results are in Table 2. Table 2 Trial Trial 2 Trial 3 Trial 4 Melting point in C Calculate the mean melting point of the hydrocarbon, leaving out any anomalous result. Give your answer to two significant figures. Mean melting point = C (2) (Total 0 marks) 3 This question is about drinking water. (a) Name two methods of treating water from rivers, lakes or the sea to produce drinking water. Tick two boxes. Anaerobic digestion Cracking Desalination Electrolysis Sterilising (2) Page 8 of 0

9 (b) The table below shows the amounts of dissolved ions in a sample of drinking water. Dissolved ion Mass in mg per dm 3 Cl 250 Na NO What is the name of the ion with the symbol Cl? Tick one box. Calcium ion Carbonate ion Chloride ion Chlorine ion () Page 9 of 0

10 (c) Use the information in the table above to complete the bar chart in Figure. Figure () (d) Look at the questions labelled A, B, C, D. A How many substances are there in drinking water? B How much fluoride is in drinking water? C Is fluoride soluble in drinking water? D Should fluoride be added to drinking water? Which one of the questions cannot be answered by science alone? Tick one box. A B C D () Page 0 of 0

11 (e) Give two reasons why the answer you have chosen cannot be answered by science alone.. 2. (2) (f) A sample of drinking water contains.5 mg of fluoride per dm 3 of water. A person drinks dm 3 of this water. The recommended daily amount of fluoride is 4.0 mg. Which calculation gives the percentage of the recommended daily amount of fluoride in dm 3 of this water? Tick one box. () Page of 0

12 (g) Figure 2 shows the effect of fluoride in drinking water on tooth decay in different age groups. Figure 2 Describe the pattern of tooth decay in Figure 2 for water without fluoride. Use data to justify your answer. (2) (h) Describe the effect of adding fluoride to drinking water for the age groups in Figure 2. (2) (Total 2 marks) 4 (a) The hydrocarbon C 6 H 34 can be cracked. Balance the equation for cracking C 6 H 34 C 6 H 34 C 2 H 4 + C 8 H 8 () Page 2 of 0

13 (b) Describe the differences between cracking and distillation. (2) (c) What type of reaction is cracking? Tick one box. Combustion Decomposition Neutralisation Precipitation () Page 3 of 0

14 (d) Ethene is used to make poly(ethene). Poly(ethene) is used to make plastic bags. the table below shows data from a Life Cycle Assessment (LCA) for a plastic bag and a paper bag. Plastic bag Paper bag Raw materials Crude oil or natural gas Wood Energy used in MJ.5.7 Mass of solid waste in g 4 50 Mass of CO 2 produced in kg Volume of fresh water used in dm A company stated: A Life Cycle Assessment shows that using plastic bags has less environmental impact than using paper bags. Evaluate this statement. Use your knowledge and the information from above the table above. (6) (Total 0 marks) Page 4 of 0

15 5 Rainwater is collected from the roofs of houses as shown in Figure. Figure (a) The water in the storage tank is not potable. What does potable mean? Tick one box. Contains dissolved substances Pure Safe to drink Tastes nice () Page 5 of 0

16 (b) Why should the water in the tank be filtered to make it potable? Tick one box. To kill microbes To remove dissolved gases To remove dissolved solids To remove undissolved solids () (c) A gas which bleaches litmus paper can be added to the water to make it potable. Name this gas and explain why it is added. (2) Page 6 of 0

17 (d) The storage tank is made from concrete reinforced with steel wire, as shown in Figure 2. Figure 2. Figure 3 shows how the distance between the steel wires affects the relative strength of the concrete. Figure 3 Use values from Figure 3 to describe the relationship shown by the graph. (2) (Total 6 marks) Page 7 of 0

18 6 All life on Earth depends on water. The figure below shows an iceberg floating on the sea. Gibas DigiPhoto/iStock/Thinkstock (a) Explain how the water molecules in the iceberg could end up as water in a lake. (4) Page 8 of 0

19 (b) Rainwater collects in rivers and lakes. Water in rivers and lakes contains materials that make the water unsafe to drink. Describe how the water from rivers and lakes is treated to make it safe to drink. (4) (Total 8 marks) 7 Iron is a metal that has many uses. (a) Iron is extracted from iron ore. Part of the process involves reduction of the ore with carbon monoxide. Iron ore contains iron oxide (Fe 2 O 3 ). Write a balanced equation for the reaction of iron oxide with carbon monoxide. (3) (b) Explain why this reaction is a redox reaction. (2) Page 9 of 0

20 Steel is an alloy of iron. Steel is used to make cars. After its useful life a car is taken to a scrapyard for recycling. (c) Suggest four benefits of recycling a car body. (4) Page 20 of 0

21 (d) Figure shows an electromagnet being used to lift a car in a scrapyard. Figure An electromagnet is made up of a solenoid. Figure 2 shows a solenoid. Figure 2 Draw the magnetic field of the solenoid on Figure 2. (2) Page 2 of 0

22 (e) In a scrapyard, an electromagnet is used to lift and release cars so they can be moved around. Suggest two ways a solenoid could be made to lift and release cars in a scrapyard. Explain why each suggestion would be useful in the scrapyard. (4) (Total 5 marks) 8 Hydrocarbons are used to make useful products. (a) What are the elements in hydrocarbons? Tick one box. Carbon and hydrogen only Carbon, hydrogen and oxygen Carbon and nitrogen only Carbon, nitrogen and oxygen () Page 22 of 0

23 (b) Table gives some information about four hydrocarbons. Table Hydrocarbon Melting point in C Boiling point in C Methane Ethene Octane Decane What are two correct statements about the four compounds? Tick two boxes. Methane has the lowest boiling point and decane has the highest melting point Methane and decane are both gases at 20 C Ethene and octane are both alkanes Decane and ethene are both liquids at 0 C Octane is liquid over a larger temperature range than methane (2) (c) Ethene can be produced from long-chain hydrocarbons by cracking. Give the conditions needed for cracking. (2) Page 23 of 0

24 (d) Poly(ethene) is a polymer made from ethene. Poly(ethene) is used to make plastic bags. Table 2 is from a life cycle assessment comparing paper bags and plastic bags. Table 2 Raw material Paper bag Wood (renewable) Plastic bag Oil or gas (non-renewable) Energy used to make in MJ.7.5 Solid waste produced in g 50 4 Carbon dioxide produced in kg Evaluate which type of bag is more environmentally friendly. Use data from Table 2 and your own knowledge to support your answer. (6) (Total marks) Page 24 of 0

25 9 Electricity in the UK is generated in many ways. The figure below shows an undersea turbine. The undersea turbine uses tidal energy to generate electricity. alex-mit/istock/thinkstock (a) What is the original source of energy for tidal power schemes? () (b) Explain two advantages of using undersea tidal turbines to generate electricity rather than burning fossil fuels. (4) Page 25 of 0

26 (c) Some power stations burn wood instead of fossil fuels to generate electricity. A coal-burning power station burns 6 million tonnes of coal per year. Coal has an average energy value of MJ per kg. Wood chip from willow trees has an energy value of 3 MJ per kg. A hectare of agricultural land can produce 9 tonnes of dry willow wood per year. If this power station burned dry willow wood instead of coal, how much agricultural land would be needed to grow the willow? Amount of land needed = hectares (3) Page 26 of 0

27 (d) The table below shows the carbon dioxide emissions of four fuels used to generate electricity. Fuel Direct CO 2 emissions in kg per MWh Lifecycle CO 2 emissions in kg per MWh Coal Natural gas Oil Wood Direct CO 2 emissions are the amounts of carbon dioxide released when the fuel is burned. Lifecycle CO 2 emissions is the total amount of carbon dioxide released during all stages from fuel extraction to when the fuel has been used. Use the data from the table above to explain why wood is considered to be a low carbon dioxide emitting fuel. (2) (Total 0 marks) Page 27 of 0

28 0 Read the information about production of copper. World demand for copper in 204 was about 22 million tonnes. World reserves of copper are about 700 million tonnes. Most of the copper today is obtained from copper ores. The ores are mined. Copper ore is heated in a furnace to produce copper sulfide. The furnace is heated by burning fossil fuels. Air is blown through the hot copper sulfide to produce copper and sulfur dioxide. Some copper is extracted from low-grade ores by phytomining. Phytomining uses plants to absorb copper compounds. The plants are burned and copper is extracted from the ashes. A scientist stated: more copper should be extracted by phytomining. Use the information to justify the scientist s statement. (Total 6 marks) Page 28 of 0

29 This question is about copper. (a) Copper can be extracted by smelting copper-rich ores in a furnace. The equation for one of the reactions in the smelting process is: Cu 2 S(s) + O 2 (g) 2 Cu(s) + SO 2 (g) Explain why there would be an environmental problem if sulfur dioxide gas escaped into the atmosphere. (2) (b) The impure copper produced by smelting is purified by electrolysis, as shown below. Copper atoms are oxidised at the positive electrode to Cu 2+ ions, as shown in the half equation. Cu(s) Cu 2+ (aq) + 2e (i) How does the half equation show that copper atoms are oxidised? () Page 29 of 0

30 (ii) The Cu 2+ ions are attracted to the negative electrode, where they are reduced to produce copper atoms. Write a balanced half equation for the reaction at the negative electrode. () (iii) Suggest a suitable electrolyte for the electrolysis. () (c) Copper metal is used in electrical appliances. Describe the bonding in a metal, and explain why metals conduct electricity. (4) (d) Soil near copper mines is often contaminated with low percentages of copper compounds. Phytomining is a new way to extract copper compounds from soil. Describe how copper compounds are extracted by phytomining. (3) Page 30 of 0

31 (e) A compound in a copper ore has the following percentage composition by mass: 55.6% copper, 6.4% iron, 28.0% sulfur. Calculate the empirical formula of the compound. Relative atomic masses (A r ): S = 32; Fe = 56; Cu = 63.5 You must show all of your working. Empirical formula = (4) (Total 6 marks) 2 This question is about metals. (a) Which unreactive metal is found in the Earth as the metal itself? Tick ( ) one box. aluminium gold magnesium () Page 3 of 0

32 (b) Complete the sentence. Aluminium is an element because aluminium is made of only one type of. () (c) Figure shows the electronic structure of an aluminium atom. (i) Use the correct words from the box to complete the sentence. electrons ions protons neutrons shells The nucleus of an aluminium atom contains and. (2) (ii) Complete the sentence. In the periodic table, aluminium is in Group. () Page 32 of 0

33 (d) Aluminium is used for kitchen foil. Figure 2 shows a symbol on a box of kitchen foil. The symbol means that aluminium can be recycled. It does not show the correct chemical symbol for aluminium. (i) What is the correct chemical symbol for aluminium?. () (ii) Give two reasons why aluminium should be recycled. (2) (e) Aluminium has a low density, conducts electricity and is resistant to corrosion. Which one of these properties makes aluminium suitable to use as kitchen foil? Give a reason for your answer. (2) (Total 0 marks) Page 33 of 0

34 3 This question is about drinking water. (a) The flow diagram below shows how water is made suitable for drinking. (i) What is removed when the water is filtered? Tick ( ) one box. Gases Liquids Solids () (ii) What is used to sterilise the water? Tick ( ) one box. Carbon Chlorine Sodium chloride () Page 34 of 0

35 (iii) Why is the water sterilised? () (b) Water can be purified by distillation. Drinking water is not usually purified by distillation because distillation is expensive. Complete the sentence. Distillation is expensive because it requires a lot of () (c) Why do some water companies add fluoride to drinking water? () (Total 5 marks) Page 35 of 0

36 4 This question is about copper. (a) Most of the copper extracted is used in electric circuits. The figure below shows how impurities change the electrical conductivity of copper. Percentage of impurities in copper Copper extracted by smelting is about 99% pure. The 99% pure copper produced by smelting is purified to % pure copper by electrolysis. Use values from the graph to explain why copper is purified to %. (2) Page 36 of 0

37 (b) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. Read the information in the box. Copper extraction World demand for copper for the year 20 was about 20 million tonnes. World reserves of copper are estimated to be 700 million tonnes. Most of the copper used is obtained from copper ores, which are mined. The copper ore chalcopyrite is heated in a furnace to produce copper sulfide, CuS The furnace is heated by burning fossil fuels. Air is then blown through the hot copper sulfide, to produce copper and sulfur dioxide. CuS + O 2 Cu + SO 2 A scientist made the statement: Copper should be recycled. Use the information in the box and your own knowledge and understanding to justify the scientist s statement. Page 37 of 0

38 Extra space (6) (c) Phytomining is used to obtain copper from land that contains very low percentages of copper compounds. Describe how copper compounds are obtained by phytomining. (3) (Total marks) Page 38 of 0

39 5 Where copper ore has been mined there are areas of land that contain very low percentages of copper compounds. One way to extract the copper is to grow plants on the land. The plants absorb copper compounds through their roots. The plants are burned to produce copper oxide. The copper oxide produced from plants can be reacted to produce copper or copper sulfate solution, as shown in Figure. Figure (a) Draw a ring around the correct answer to complete each sentence. (i) Copper ores contain enough copper to make extraction of the metal carbon neutral. economical. reversible. () (ii) Using plants to extract metals is called photosynthesis. phytomining. polymerisation. () (iii) Copper oxide reacts with carbon to produce copper and carbon dioxide. oxygen. sulfur dioxide. () (b) Copper is produced from copper sulfate solution by displacement using iron or by electrolysis. (i) Complete the word equation. copper sulfate + iron + (2) Page 39 of 0

40 (ii) Figure 2 shows the electrolysis of copper sulfate solution. Figure 2 Why do copper ions go to the negative electrode? () (c) Suggest two reasons why copper should not be disposed of in landfill sites. (2) (Total 8 marks) Page 40 of 0

41 CuO + C + CO 2 (2) 6 Where copper ore has been mined there are areas of land that contain very low percentages of copper compounds. One way to extract the copper is to grow plants on the land. The plants absorb copper compounds through their roots. The plants are burned to produce copper oxide. The copper oxide produced from plants can be reacted to produce copper or copper sulfate solution, as shown in Figure. Figure (a) (i) Complete the sentence. Using plants to extract metals is called. () (ii) Suggest two reasons why copper from these areas of land is not extracted by smelting. (2) (iii) Complete and balance the chemical equation for the reaction of copper oxide with carbon. Page 4 of 0

42 (b) Copper is produced from copper sulfate solution by displacement using scrap iron or by electrolysis. (i) Use the Chemistry Data Sheet to help you to answer this question. Give two reasons why scrap iron is used to displace copper. (2) (ii) Figure 2 shows the electrolysis of copper sulfate solution. Figure 2 Describe what happens to the copper ions during electrolysis. (2) (Total 9 marks) Page 42 of 0

43 7 Water in Britain is taken from reservoirs to use as drinking water. KatieJonesPhotography/iStock/Thinkstock (a) What are the two main steps used to treat water from reservoirs? Give one reason for each step. (4) (b) Some people use water filters to treat water before drinking it. (i) Water filters remove hardness from hard water. What is in water filters that removes hardness from water? () Page 43 of 0

44 (ii) Suggest why water filters used in the home contain particles of silver. () (c) Pure water can be produced by distillation. Why is distillation not usually an economic method of treating water for drinking? () (d) Drinking hard water has health benefits. State one health benefit of drinking hard water. () (Total 8 marks) 8 Most water contains dissolved compounds. The concentrations of these dissolved compounds are higher in sea water than in drinking water. (a) (i) Draw a ring around the correct answer to complete the sentence. distillation. Pure water can be obtained from sea water by filtration. neutralisation. () (ii) What is the boiling point of pure water? C () Page 44 of 0

45 (b) A student wanted to find out how much solid was dissolved in sea water. This is the method the student used: measure the mass of an empty evaporating basin measure 25 cm 3 of sea water and pour it into the evaporating basin heat the evaporating basin gently until all of the water has evaporated measure the mass of the evaporating basin containing the solid residue. (i) What piece of apparatus would be suitable for measuring 25 cm 3 of sea water? () (ii) How could the student check that all of the water had evaporated? (2) (iii) The results the student obtained using 25 cm 3 of sea water are: mass of empty evaporating basin = 23.2 g mass of evaporating basin and dry solid residue = g Calculate the mass of solid dissolved in 000 cm 3 of the sea water. Mass dissolved in 000 cm 3 = g (2) (c) In many countries chlorine is added to drinking water supplies. Why is chlorine added to drinking water? () Page 45 of 0

46 (d) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. Compounds containing fluoride ions are added to some drinking water supplies. Many scientists have done research into the effects of fluoride ions in drinking water. Graphs, 2 and 3 show some of the results obtained. Page 46 of 0

47 Evaluate the advantages and disadvantages of adding fluoride ions to drinking water. You should support your answer with evidence from all three graphs. (6) (Total 4 marks) Page 47 of 0

48 9 Metals are extracted from their ores. Many copper ores contain only 2% of copper compounds. (a) Copper is now extracted from ores containing a low percentage of copper compounds. Suggest two reasons why. (2) (b) Chalcocite, an ore of copper, contains copper sulfide. The flow diagram shows how copper metal is extracted from chalcocite. (i) Suggest one reason why it is difficult to dispose of the waste rock. () Page 48 of 0

49 (ii) The reaction in the furnace could cause environmental pollution. Explain how. (2) (iii) The extraction of pure copper is expensive. Give one reason why. () (iv) Pure copper is produced by electrolysis of copper sulfate solution. Which electrode do the copper ions move towards? Give a reason for your answer. (2) (v) Large areas of land are contaminated with copper compounds. Phytomining can be used to remove these copper compounds from the land. What is used in phytomining to remove copper compounds from the land? () (Total 9 marks) Page 49 of 0

50 20 The graph shows the boiling points of the halogens. (a) Use the graph to help you answer these questions. (i) Use the correct answer from the box to complete the sentence. gas liquid solid At room temperature chlorine is a. () (ii) Describe the trend in boiling point from fluorine to iodine. () (b) Chlorine reacts with metals to produce metal chlorides. (i) When a chlorine atom forms a chloride ion it gains one electron. What is the charge on a chloride ion? () (ii) Write a word equation for the reaction between sodium and chlorine. () (c) In the UK water companies add chlorine to tap water. Why is chlorine added to tap water? () Page 50 of 0

51 (d) Water companies add fluoride to tap water in some parts of the UK. Fluoride is added to improve dental health. Suggest one reason why some people are against adding fluoride to tap water. () (Total 6 marks) 2 Cans for food and drinks are made from steel or aluminium. The main metal in steel is iron. By Sun Ladder (Own work) [CC-BY-SA-3.0 or GFDL], via Wikimedia Commons (a) Iron is extracted by heating a mixture of iron oxide and carbon in a blast furnace. (i) Name this type of reaction. () (ii) Balance the symbol equation for this reaction. 2Fe 2 O 3 + C Fe + CO 2 () Page 5 of 0

52 (b) Aluminium ore, bauxite, contains aluminium oxide, iron oxide and silicon dioxide. Aluminium is extracted by electrolysis of aluminium oxide. The 'red mud' which is dumped in very large ponds contains: Name of solid Percentage (%) Aluminium oxide 0 Iron oxide 65 Silicon dioxide 25 (i) 00 tonnes of bauxite produced 50 tonnes of pure aluminium oxide and 50 tonnes of 'red mud'. What percentage of aluminium oxide did the bauxite contain? Answer = % () (ii) Apart from the solids shown in the table, name one other substance that would be in the 'red mud'. () Page 52 of 0

53 (iii) The purification of the aluminium oxide is usually done near to the bauxite quarries. Suggest one reason why. () (c) Aluminium is used to make many things including cans. During one year in the USA: 00 billion aluminium cans were sold 55 billion aluminium cans were recycled. Give one environmental impact of recycling aluminium cans and one ethical or social impact of recycling aluminium cans. Environmental Ethical or social (2) (Total 7 marks) Page 53 of 0

54 22 Read the article and then answer the questions. Supermarkets launch eco-friendly plastic milk bags. Could this be the end of the milk bottle? Milk bottles are made from glass or from plastic. Glass milk bottles contain 0.5 litres of milk. When the milk is used up the empty bottles are returned to be re-used. Glass milk bottles are re-used 24 times on average. The glass to make new milk bottles is produced when a mixture of sand, limestone, soda and recycled glass is heated to about 600 C in a furnace. There are almost unlimited amounts of the raw materials needed to produce this glass. About 35% of used glass is recycled. The most common plastic milk bottles contain 2 litres of milk. When the milk is used up the empty bottles are discarded as waste. The plastic used to make these milk bottles is poly(ethene). Poly(ethene) is produced from crude oil by first using fractional distillation, then cracking the naphtha fraction and finally polymerising the ethene. About 5% of used poly(ethene) is recycled. The new plastic milk bags contain 2 litres of milk. The milk bags are also made from poly(ethene). A milk bag uses 75% less poly(ethene) than is used to make the poly(ethene) milk bottles. When the milk is used up the empty bags are discarded as waste. (a) Describe what happens in fractional distillation so that fractions, such as naphtha, are separated from crude oil. (3) Page 54 of 0

55 (b) Supermarkets claim that using milk bags instead of milk bottles would have less environmental impact. Do you agree with this claim? Use the information in the article and your knowledge and understanding to make appropriate comparisons to justify your answer. (4) (Total 7 marks) Page 55 of 0

56 23 The flow diagram shows the main stages used to extract a metal from its ore. mining the ore purifying the ore extracting the metal The table shows some information about three metals. Metal Metal ore Purified ore % of metal in the ore % of metal in the Earth s crust aluminium bauxite aluminium oxide, Al 2 O copper chalcocite copper sulfide, Cu 2 S iron haematite iron oxide, Fe 2 O (a) Use the information in the table and your knowledge and understanding to help you to answer the questions. (i) Suggest why purifying the copper ore produces large quantities of waste. () (ii) Suggest why the annual world production of iron is forty times greater than that of aluminium. () Page 56 of 0

57 (b) Aluminium is used for drinks cans. Aluminium is extracted from its purified ore by electrolysis. (i) Suggest why the aluminium produced in the electrolysis cell is a liquid. () (ii) In this electrolysis, aluminium and oxygen gas are produced from the aluminium oxide. Use the information in the diagram to suggest why most of the waste gas is carbon dioxide and not oxygen. (2) (iii) Aluminium is the most abundant metal in the Earth s crust. Suggest two reasons why we should recycle aluminium drinks cans.. 2. (2) (Total 7 marks) Page 57 of 0

58 24 Supermarkets in the UK have been advised by the Government to stop giving plastic bags to customers. The Government states that this is because plastic bags use up resources that are not renewable and that the manufacture of plastic bags produces carbon dioxide. Most of these plastic bags are made from poly(ethene). The table shows methods to deal with large numbers of used plastic bags. Method Reused Recycled Burned Dumped Description of what happens to the plastic bag used again by the customer collected, transported, washed and melted to make new plastic items collected, transported and burnt to release heat energy mixed with other household waste, collected, transported and disposed of at a landfill site Use the information and your knowledge and understanding to briefly give one advantage and one disadvantage for each of these methods. Reused Recycled Burned Dumped (4) (Total 4 marks) Page 58 of 0

59 25 Good quality water is essential for life. (a) In the United Kingdom, water is filtered and treated with chlorine to make it safe to drink. Explain why the water is: filtered treated with chlorine. (2) Page 59 of 0

60 (b) Millions of people in Bangladesh drink water from wells that contain high levels of arsenic. Arsenic is poisonous. The World Health Organisation recommends that there should be no more than 0.0 mg of arsenic per litre in drinking water. The table gives some information about two instrumental methods of testing for arsenic. Factor to consider Laboratory Instrumental Method Portable Instrumental Method Cost of equipment Skill level of technician Highly skilled where test is done Little training needed Laboratory only Anywhere Time to prepare the instrument for the test 5 minutes 0 seconds Sensitivity of the instrument mg of arsenic per litre of water 0. mg of arsenic per litre of water (i) Use the information in the table to give two advantages and one disadvantage of using the Portable Instrumental Method compared with the Laboratory Instrumental Method. (3) Page 60 of 0

61 (ii) The information about these two instrumental methods was provided by the Professional Institute of Water Engineers (PIWE). The Institute has no connection with the companies that make these instruments. Suggest why many people would accept the views of PIWE rather than the views of the companies that make the instruments. () (Total 6 marks) 26 Read the following information and then answer the questions. Chlorine for better, for worse? Chlorine is used to make bleaches, plastics and medicines. Swimming pool water is often treated with chlorine. Chlorine is used to make water safe to drink. It is relatively cheap and easy to use. People who drink untreated water risk dying from typhoid and cholera. However, chlorine is a poisonous chemical. It causes breathing difficulties and can kill people. Some people are also allergic to chlorine. (a) How does chlorine make water safe to drink? () Page 6 of 0

62 (b) The amount of chlorine in swimming pool water should be carefully monitored and controlled. Explain why. (2) (c) Developing countries are likely to choose chlorination as their method of making water safe to drink. Suggest why. () (d) A government is setting up an enquiry into the safety of using chlorine. (i) Suggest why people from all political parties should be represented. () (ii) Suggest why the opinion of a well-respected scientist might change the outcome of any discussion. () Page 62 of 0

63 (iii) The decision taken about the safety of using chlorine should be based on evidence and data rather than on hearsay and opinion. Suggest why. () (Total 7 marks) 27 Iron is produced by reacting a mixture of haematite and coke in a blast furnace. Haematite is an ore of iron containing iron oxide (Fe 2 O 3 ). Coke is made from coal and is almost pure carbon. (a) (i) The coke burns in air. This reaction heats the furnace to above 300 C. Complete the chemical equation for carbon reacting with oxygen to form carbon dioxide. + O 2 CO 2 () (ii) Carbon monoxide is also formed in the furnace. Carbon monoxide reacts with iron oxide to produce iron and carbon dioxide. iron oxide + carbon monoxide iron + carbon dioxide Complete and balance the chemical equation for the production of iron. Fe 2 O 3 + 3CO + (2) Page 63 of 0

64 (iii) Iron from a blast furnace is called cast iron and contains about 4% carbon. Why is pure iron softer than cast iron? () (b) Steel is made by reducing the percentage of carbon in cast iron and then adding different metals to form the type of steel required. In the UK we use about.8 billion steel cans every year but only 30% of these are recycled. Recycling reduces waste. Producing steel from recycled cans requires only 25% of the energy needed to make steel from iron ore. Give three environmental benefits of recycling a higher percentage of used steel cans (3) (Total 7 marks) 28 Plastics are used to make many everyday items, such as the body of the kettle. Page 64 of 0

65 (a) Complete the sentences by drawing a ring around the correct words. (i) The plastic is made from many small molecules called catalysts monomers polymers () (ii) Propene is produced by cracking some of the fractions that are crude oil separated from limestone metal ores () (b) After a few years the kettle no longer worked. Some parts of the kettle are made of plastic. Some parts of the kettle are made of stainless steel. The owner of the kettle disposed of it in a landfill site. Consider these statements. Suggest three reasons why the kettle should not be disposed of in a landfill site (3) (Total 5 marks) Page 65 of 0

66 29 Aluminium has many uses because of its low density, good electrical conductivity, flexibility and resistance to corrosion. The main steps in the extraction of aluminium are shown in the flow chart. (a) Use the information in the flow chart to suggest the benefits of recycling aluminium. (3) (b) Pure aluminium is rarely used for the construction of large objects. Small amounts of other metals are usually mixed with aluminium. Explain why. (2) (Total 5 marks) Page 66 of 0

67 30 Good quality water is needed for a healthy life. In the United Kingdom, obtaining safe water for drinking is as simple as turning on a tap. The water is made safe to drink by water companies. However, in many parts of Africa and Asia, water used for drinking is contaminated and untreated. It is estimated that 2.2 million people die each year as a result of drinking contaminated water. DADA DANESHANANDA, Man with filtered water from the Mafi-Zongo water project. (a) Sea water is not used as drinking water. Suggest why. () (b) Explain why water for drinking is filtered and then treated with chlorine. (2) (Total 3 marks) Page 67 of 0

68 3 Good quality water is needed for a healthy life. In the United Kingdom, obtaining safe water for drinking is as simple as turning on a tap. The water is made safe to drink by water companies. However, in many parts of Africa and Asia, water used for drinking is contaminated and untreated. It is estimated that 2.2 million people die each year as a result of drinking contaminated water. DADA DANESHANANDA, Man with filtered water from the Mafi-Zongo water project. Efforts are being made to solve this problem and more water is being treated. Describe how water in the United Kingdom is treated. Explain how this makes it safe to drink. (Total 3 marks) 32 Many everyday items are made from iron. (a) Haematite is an ore of iron. Haematite contains iron oxide, Fe 2 O 3. Page 68 of 0

69 (i) What is the meaning of the term ore? () (ii) Iron can be produced by reacting iron oxide with carbon in a blast furnace. What type of reaction produces the iron? () (iii) The word equation for this reaction is: iron oxide + carbon iron + carbon dioxide Complete and balance the symbol equation for this reaction. Fe 2 O 3 + C + (2) (b) Pure iron is relatively soft and not very strong. The iron from the blast furnace is very hard and brittle. It contains about 4% carbon and is used as cast iron. Explain the differences in the properties of pure iron and cast iron by referring to the diagrams. (3) Page 69 of 0

70 (c) The diagram shows the way in which iron is extracted, used and recycled. Explain why the recycling of iron is necessary for sustainable development. (3) (Total 0 marks) 33 Copper is a widely used metal. The main ore of copper contains copper sulfide. Copper can be extracted from copper sulfide in a three stage process. Cu 2 S + O 2 CuO + SO 2 () Page 70 of 0

71 (ii) Explain why there would be an environmental problem if the gas from this reaction were allowed to escape into the atmosphere. (2) (b) In the second stage copper oxide, CuO, is reduced using carbon. Describe and explain what happens during this reaction. (2) (c) During the third stage the copper can be purified as shown in the diagram. (i) What is the name of the type of process used for this purification? () (ii) Give one use of purified copper. () Page 7 of 0

72 (d) Copper-rich ores are running out. New ways of extracting copper from low grade ores are being researched. Recycling of copper may be better than extracting copper from its ores. Explain why. (3) (Total 0 marks) 34 The electrolysis of sodium chloride solution is an important industrial process. The apparatus shown below can be used to show this electrolysis in the laboratory. (a) Name gas A. () Page 72 of 0

73 (b) Chlorine is produced at the positive electrode. Describe and give the result of a chemical test to prove that the gas is chlorine. (2) (c) Chloride ions move to the positive electrode. Explain why. () (d) A small quantity of chlorine is added to drinking water. Explain why. () (e) The solution around the negative electrode becomes alkaline. Name the ion which makes the solution alkaline. () (Total 6 marks) Page 73 of 0

74 35 (a) Aluminium is more expensive than iron. Why is aluminium and not iron used for the central core in power cables? (2) Page 74 of 0

75 (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) (Total 7 marks) Page 75 of 0

76 Mark schemes (a) electrodes connected to d.c. power supply by wires for this diagram ignore the material used for the electrodes as long as they are made from carbon or metals that are inert electrodes labelled anode (+) and cathode ( ) (b) copper ions cause the blue colour answer must be in terms on copper ions copper ions are reduced / converted to copper ions so the concentration of copper ions decreased if no other mark awarded allow mark for copper ions are used up during electrolysis (c) copper ions are positive so are attracted to the inert cathode or inert negative electrode copper ions gain electrons at the inert cathode or inert negative electrode so they are reduced to form copper atoms (d) 50 cm 3 contains 4 g CuSO 4 M r CuSO 4 = g CuSO 4 reacts with 56 g Fe =.40(43877) =.4 (g) accept.4(g) with no working shown for 4 marks allow.40(43887) without working shown for 3 marks [3] 2 (a) Flask Page 76 of 0

77 (b) Fractional distillation (c) A boiling in this order (d) (e) (f) B condensing Pentane Formulation the fuel is a pure compound and crude oil is a mixture or the fuel is made up of four hydrocarbons allow crude oil contains a large number of compounds and the fuel contains four and crude oil could have many more (g) ( / 3) = allow ( / 4 =) 39(.25) for mark [0] 3 (a) Desalination Sterilising (b) Chloride ion (c) correct bar for NO 3 - (d) D Page 77 of 0

78 (e) (f) (g) (h) any two from: people have the right to choose (opinion) ethical / moral question cannot be tested by experiment the percentage tooth decay increases with age by 4 % for each increasing age group reduces tooth decay (for all age groups) 2 greater reduction in older people [2] 4 (a) 4 (C 2 H 4 ) (b) (c) cracking involves a catalyst distillation does not or distillation does not involve a chemical change but cracking does Decomposition Page 78 of 0

79 (d) Level 3 (5 6 marks): A logically structured evaluation with links involving several comparisons. Nearly all points made are relevant and correct. Level 2 (3 4 marks): Some valid comparisons made between the two types of bag. There may be some incorrect or irrelevant points. Level ( 2 marks): A vague response with few correct and relevant points and with no direct comparisons. 0 marks: No relevant content Indicative content Accept converse in terms of plastic bags for all statements Paper bags are made from a renewable resource Plastic bags are made from a finite resource Paper bags require more energy to manufacture Paper bags produce more waste Paper bags are biodegradable Paper bags create more CO 2 CO 2 created by paper bags offset by photosynthesis in growing wood Paper bag requires much more fresh water Paper bags cannot be recycled Agree because non-renewability less important than other factors or disagree because of converse or can t say because data inconclusive / incomplete 6 [0] 5 (a) Safe to drink (b) To remove undissolved solids (c) the gas is chlorine / Cl 2 (d) which sterilises water as distance between steel increases strength of concrete decreases change above and change below.0 cm separation is compared and described must refer to graph values for this mark [6] Page 79 of 0

80 6 (a) Level 2 (3 4 marks): A detailed and coherent explanation of how the water molecules transfer through the water cycle from one form / area to another. Logical links are made between the general details of the water cycle to the context of the iceberg. Level ( 2 marks): Simple relevant facts stated about the water cycle. Details may be missing and any links made with the context of the iceberg may be inconsistent or vague. 0 marks: No relevant content. (b) Indicative content water in the iceberg is in its solid state when the iceberg melts water is in its liquid form and the water molecules go into the sea water evaporates from the surface of the sea so the water molecules go into the air as vapour as the air rises it cools so water vapour condenses into droplets in clouds clouds can be moved around the world by winds droplets then fall as rain / snow / hail / precipitation into a lake solid materials removed by filtration or by passing through filter beds microbes 4 are killed by sterilisation allow killed by chlorine / ozone / ultraviolet light [8] 7 (a) Fe 2 O CO 2Fe + 3 CO 2 correct formulae of reactants correct formulae of products correct balancing (b) iron loses oxygen reduction carbon gains oxygen oxidation Page 80 of 0

81 (c) any four from: resources for manufacture are limited recycling reduces the use of resources reduces energy consumption in extraction / manufacture reduces waste from processing and extraction reduces environmental impact of extraction 4 (d) field lines going through and around coil correct directional arrows (e) any two from: mark for suggestion, mark for correctly linked explanation use many coils or tight coils or long wire () to give a strong magnetic field for lifting heavy objects () explanation must be correctly linked to the suggestion to gain the mark or add an iron core to increase field circuit for lifting or include a switch in circuit so can drop / pick up cars max. 4 [5] 8 (a) Carbon and hydrogen only (b) Methane has the lowest boiling point and decane has the highest melting point Octane is liquid over a larger temperature range than methane (c) heat / steam catalyst Page 8 of 0

82 (d) Level 3 (5 6 marks): A detailed and coherent evaluation is provided that considers a range of relevant points, quotes relevant data from the table and comes to a conclusion consistent with the reasoning. Level 2 (3 4 marks): An attempt to describe relevant points which comes to a conclusion. The logic and use of data may be inconsistent at times but builds towards a coherent argument. Level ( 2 marks): Discrete, relevant points made. The logic may be unclear and the conclusion, if present, may not be consistent with the reasoning. 0 marks: No relevant content. Indicative content conclusion as to which bag is more environmentally friendly Points that may be used in argument Paper bags are made from a renewable resource (wood) Paper bags more sustainable Paper bags are biodegradable Plastic bags are made from a finite resource (oil or gas) Plastic bags not sustainable Paper bags require more energy to manufacture (.7 MJ compared with.5 MJ) Paper bags produce more waste (50 g compared with 4 g) Paper bags create less CO 2 than plastic bags So manufacture of plastic bags has more effect on global warming / climate change / environmental effects Plastic bags can be recycled Recycling reduces use of energy sources in manufacture justified 6 [] 9 (a) gravity (of moon and sun) Page 82 of 0

83 (b) any two from: mark for statement, mark for correctly linked reason tidal energy is renewable () so won t run out like fossil fuels () or doesn t emit carbon dioxide so won t contribute to global warming / climate change or doesn t emit oxides of sulfur or nitrogen so doesn t cause acid rain or doesn t use fossil fuels so less impact on environment of extraction / transport or (c) (d) doesn t produce particulates so less effect on health / environment coal consumption per year = million = MJ hectare of willow will produce = MJ per year so need = (hectares) allow with no working shown for 3 marks although has higher direct emissions than other fuels Max. 4 it has much lower lifetime emissions [0] Page 83 of 0

84 0 Level 3 (5 6 marks): A detailed, coherent and logical justification of the scientist s statement, with relevant links made between statements in the question, phytomining and the effects of other methods of metal production on the environment. Level 2 (3 4 marks): An attempt to justify the scientist s statement is made, with some attempt at linking statements. The logic may be inconsistent at times but builds towards a coherent argument. Level ( 2 marks): Discrete relevant points made. The logic may be unclear and may not be consistent with the reasoning. Links are not made. 0 marks: No relevant content Indicative content phytomining conserves supplies of ores copper will be available for longer as at present rate of use copper ores will run out in about 35 years phytomining conserves supplies of fossil fuels or energy less fuel used at a lower cost mining scars landscape or produces noise pollution mining destroys wildlife habitats with more phytomining less need to mine ores with phytomining less habitat destroyed or less scarring of landscape with phytomining less need to use landfill for waste burning fossil fuels produces carbon dioxide / greenhouse gas burning fossil fuels causes global warming or climate change extraction from ores produces sulfur dioxide which causes acid rain [6] (a) because sulfur dioxide causes acid rain which kills fish / aquatic life or dissolves / damages statues / stonework or kills / stunts growth of trees if no other mark awarded then award mark for sulfur dioxide is toxic or causes breathing difficulties. (b) (i) electrons are lost (ii) (iii) Cu e Cu allow Cu 2+ Cu 2e ignore state symbols copper sulfate allow any ionic copper compound Page 84 of 0

85 (c) (d) (lattice of) positive ions delocalised electrons accept sea of electrons (electrostatic) attraction between the positive ions and the electrons electrons can move through the metal / structure or can flow allow electrons can carry charge through the metal / structure if wrong bonding named or described or attraction between oppositely charged ions then do not award M or M3 MAX 2 (copper compounds are absorbed / taken up by) plants allow crops which are burned the ash contains the copper compounds do not award M3 if the ash contains copper (metal) (e) / A r 55.6 / / / 32 moles ratio 3 3 formula Cu 3 FeS 3 award 4 marks for Cu 3 FeS 3 with some correct working award 3 marks for Cu 3 FeS 3 with no working if the answer is not Cu 3 FeS 3 award up to 3 marks for correct steps from the table apply ecf if the student has inverted the fractions award 3 marks for an answer of CuFe 3 S 4 [6] 2 (a) gold (b) atom (s) Page 85 of 0

86 (c) (i) protons any order allow proton neutrons allow neutron (ii) 3 / three (d) (i) Al ignore any numbers / charges (ii) any two from: limited resource expensive in terms of energy / mining effects on the environment, such as, landfill, atmospheric pollution, quarrying allow uses a lot of energy to extract. 2 (e) resistant to corrosion does not react (with water or food) allow one mark for low density with a suitable reason given [0] 3 (a) (i) Solids (ii) (iii) Chlorine kill microbes / bacteria allow to make the water safe to drink ignore disinfect ignore remove / get rid of microbes (b) energy allow heat Page 86 of 0

87 (c) improve dental health allow reduce tooth decay allow (local) government requirement allow help teeth [5] 4 (a) pure copper is twice as good a conductor as 99% pure copper accept reverse argument accept answers quoting 2 correct values from the graph scores 2 qualitative answer (e.g. pure copper is a better conductor than impure copper) scores or answers quoting a conductivity value from the graph scores 2 Page 87 of 0

88 (b) Marks awarded for this answer will be determined by the Quality of Communication (QC) as well as the standard of the scientific response. 0 marks No relevant content Level ( 2 marks) Simple list of a limited number of points given, with no linking between ideas Level 2 (3 4 marks) A broader set of points made. There will probably not be links between ideas Level 3 (5 6 marks) Answer includes linking between ideas, showing the consequence of either not recycling or the advantage of recycling. Answers such as less fossil fuel needed so less carbon dioxide produced or less carbon dioxide produced so less global warming examples of the points made in the response resources (recycling) conserves supplies of ores copper available for longer as (at present rate of use) copper ores will run out in about 35 years (recycling) conserves supplies of fossil fuels or energy less fuel used at a lower cost land pollution mining scars landscape or produces noise pollution mining destroys wildlife habitats (recycling) less need to mine ores / fossil fuels so less habitat destroyed or less scarring of landscape (recycling) less need to use landfill for waste (c) atmospheric pollution burning fossil fuels produces carbon dioxide / greenhouse gas which (may) cause global warming or climate change extraction produces sulfur dioxide which causes acid rain which can kill trees / fish grow plants then plants are burned accept plants absorb copper (through roots) 6 ash (from burning) contains copper compounds [] Page 88 of 0