(1) (1) The waste gases from the chimney are monitored. One toxic gas that should not be released is carbon monoxide

Transcription

1 Q. Most power stations burn coal to generate electricity. Burning coal gives off sulfur dioxide gas which can be removed from the waste gases by using limestone. This prevents sulfur dioxide from entering the atmosphere and causing acid rain. One disadvantage of using limestone in a power station is that it releases locked up carbon dioxide into the atmosphere. (a) How does the limestone used in a power station: (i) release carbon dioxide () remove sulfur dioxide? () (b) The waste gases from the chimney are monitored. One toxic gas that should not be released is carbon monoxide. Explain how carbon monoxide would be formed Page of 86

2 (c) The use of limestone in a power station releases locked up carbon dioxide into the atmosphere. (i) Explain the meaning of locked up carbon dioxide. Why does the release of this carbon dioxide cause an environmental problem? () (Total 7 marks) Q. In a quarry, limestone is blasted into pieces by explosives. The pieces of limestone are taken from the quarry by lorries. (a) Draw a ring around the correct word in the box to complete the sentence. building Limestone can be used as a plastic material. smart () Page of 86

3 (b) Tick ( ) one possible advantage for people who live near to the limestone quarry. Advantage Tick ( ) causes more traffic provides jobs attracts tourists to the area () (c) Give two types of pollution that would be caused by the limestone quarry (d) Limestone contains calcium carbonate (CaCO 3 ). Complete the two empty boxes in the table about the formula of calcium carbonate. Name of element Symbol for the element Number of atoms in the formula calcium Ca carbon C oxygen (e) Lorries take some of the limestone to be heated in a lime-kiln. Calcium carbonate, in the limestone, decomposes when heated. Use the balanced chemical equation to help you complete the word equation for the decomposition of calcium carbonate. CaCO 3 CaO + CO calcium carbonate... + carbon dioxide () (Total 7 marks) Page 3 of 86

4 Q3. A company wants to extract limestone from an area of natural beauty. The Government has granted permission for the company to take and analyse samples of limestone. The company selects four sites, A, B, C and D, within the area and takes four samples from each site. (a) The limestone is analysed by: heating 5 g of each sample for 30 minutes allowing the sample to cool in a dry, argon atmosphere weighing the solid remaining The table shows the company s results. Site Mass of solid remaining in g Sample Sample Sample 3 Sample 4 A B C D Limestone is a rock containing calcium carbonate, CaCO 3 If the limestone is pure calcium carbonate then the mass of solid remaining would be.80 g. Why does the mass of limestone decrease when it is heated? () Page 4 of 86

5 (b) Suggest and explain why the solid remaining was cooled in a dry, argon atmosphere (c) Which site, A, B, C or D, would you choose for extracting limestone? Give the advantages and disadvantages for your chosen site. You must explain why you chose this site. My chosen site is (4) (Total 7 marks) Page 5 of 86

6 Q4. Limestone is mainly calcium carbonate, CaCO 3 The flow diagram represents how calcium oxide (quicklime) is made when calcium carbonate (limestone) is heated in a lime kiln. (a) (i) How many elements is calcium carbonate, CaCO 3, made from? () The main gases leaving the lime kiln are nitrogen and carbon dioxide. Explain why. (3) Page 6 of 86

7 (b) Calcium oxide (quicklime) is used in self-heating cans. The diagram shows a self-heating can made to warm baked beans. To warm the baked beans the metal pin is pushed through the seal and foil separator. The foil separator breaks allowing water to mix with the calcium oxide (quicklime). Describe what happens when water mixes with calcium oxide (Total 6 marks) Q5. Limestone is mainly calcium carbonate, CaCO 3 (a) Complete the two empty boxes in the table. Symbol Element Number of atoms in the formula CaCO 3 Ca calcium C carbon... O oxygen... Page 7 of 86

8 (b) The diagram shows a lime kiln. A lime kiln is used to heat limestone to make quicklime. Use the diagram to help you to answer these questions. Page 8 of 86

9 (i) Draw a line from each substance to the name of the main chemical(s) that the substance contains. Substance Name of the main chemical(s) calcium carbonate air calcium oxide quicklime methane nitrogen and carbon dioxide waste gases nitrogen and oxygen (3) A mixture of methane and air is used in the lime kiln. Explain why. Page 9 of 86

10 (c) Tick ( ) two uses of limestone. Use of limestone Tick ( ) as a building material to make poly(ethene) as a fuel to make cement (Total 9 marks) Q6. Calcium carbonate is found in limestone. Limestone is used as a building material. Limestone is also used to make calcium oxide and calcium hydroxide. (a) Limestone is heated to make calcium oxide. (i) Calcium oxide reacts with a substance to produce calcium hydroxide. Name the substance. () Calcium hydroxide reacts with a substance to produce calcium carbonate. Name the substance. () (b) Limestone reacts with acids. (i) Balance the chemical equation for the reaction of calcium carbonate with hydrochloric acid. CaCO 3 + HCl CaCl + CO + H O () Buildings made from limestone are affected by the products from burning fossil fuels containing sulfur. Explain why. Page 0 of 86

11 (c) When a mixture of limestone and clay is heated in a rotary kiln cement is produced. Burning a mixture of methane and air heats the kiln. Clay does not decompose in the kiln. (i) Carbon dioxide is one of the main gases in the mixture of gases coming out of the kiln. Give two reasons why. Name the other main gas in the mixture of gases coming out of the kiln. Give a reason why there is a high percentage of this gas in the mixture of gases coming out of the kiln. Name of gas... Reason... (Total 9 marks) Page of 86

12 Q7. Human stomachs contain hydrochloric acid. Stomach ache can be caused by too much acid in the stomach. Indigestion tablets can be used to reduce the amount of acid in the stomach. (a) The graph shows how the volume of carbon dioxide produced changes with time, after some calcium carbonate is added to hydrochloric acid. (i) Complete the sentence to explain what happens between O and P. Between O and P the calcium carbonate and hydrochloric acid... () Complete the sentence to explain what happens at P. At P the calcium carbonate and hydrochloric acid... because... (iii) Describe the test for carbon dioxide gas. Test... Result of the test... Page of 86

13 (b) Calcium carbonate is found in limestone. Limestone is removed from the ground by quarrying. Photograph supplied by Stockbyte/Thinkstock Tick ( ) one advantage and tick ( ) one disadvantage of quarrying limestone. Statement Quarrying limestone destroys the shells and skeletons of marine organisms that formed the limestone. Quarrying limestone releases dust, and lorries release carbon dioxide from burning diesel fuel. Quarrying limestone provides building materials, employment and new road links. Quarrying limestone removes ores from the ground. Advantage Tick ( ) Disadvantage Tick ( ) (Total 7 marks) Page 3 of 86

14 Q8. In the UK, railway sleepers were made from wood. They are now often made from concrete. A scientist was asked to find the best concrete mixture to use so that railway sleepers would not break easily.the scientist made: a mould to make small models of concrete sleepers concrete mixtures using crushed rock, sand, cement and water the equipment shown to add 0. kg masses until the model sleeper broke. The scientist s results are shown in the table. Concrete mixture in % by volume Total mass added to break the model sleeper in kg Cement Sand Crushed rock Test Test Test 3 Test 4 Mean (a) Calculate the mean total mass added to break the model sleeper that has 0 % cement by volume Mean =... kg Page 4 of 86

15 (b) State one conclusion that the scientist could make from these results () (c) The scientist sent the results in a report to a company that makes full-size concrete railway sleepers. (i) Suggest two other factors that the company should take into consideration before deciding which mixture to use to make a full-size concrete railway sleeper. The scientist s report claimed that using concrete sleepers instead of wooden sleepers would have less environmental impact. Do you agree with the scientist s claim? Use your knowledge and understanding to justify your answer. Remember to compare using concrete with using wood for the sleepers. (4) (Total 9 marks) Page 5 of 86

16 Q9. In the UK, railway sleepers are often made from concrete. A scientist was asked to find the best concrete mixture to use so that railway sleepers would not break easily. The scientist made: a mould to make small models of concrete sleepers concrete mixtures using crushed rock, sand, cement and water the equipment shown to add 0. kg masses until the model sleeper broke. The scientist s results are shown in the table. Concrete mixture in % by volume Total mass added to break the model sleeper in kg Cement Sand Crushed rock Test Test Test 3 Mean (a) (i) Calculate the mean total mass added to break the model sleeper that has 0% cement by volume. Mean =... kg () Page 6 of 86

17 Choose one result in the table that the scientist should check and test again. Result: % cement by volume... Test number... Explain why you chose this result. (iii) What is the relationship between the total mass to break the model sleeper and the percentage (%) of cement by volume in the concrete mixture? () (iv) Suggest one other variable that the scientist should have recorded in the table of results. () (b) The scientist thought that full-size railway sleepers should be made from 30% cement, 50% sand and 0% crushed rock. What other information about these three materials is needed before the scientist recommends using this mixture to make a full-size railway sleeper? (Total 7 marks) Page 7 of 86

18 Q0. Limestone is used as a building material. Acid rain erodes limestone. (a) Limestone contains calcium carbonate. The symbol equation for the reaction of calcium carbonate with hydrochloric acid is shown. CaCO 3 (s) + HCl(aq) CaCl (aq) + H O(l) + CO (g) Describe a test to show that carbon dioxide is produced in this reaction. Give the result of the test. (b) Gases from vehicle exhausts produce sulfuric acid and nitric acid. A student investigated the reaction of these two acids with calcium carbonate (limestone). The type of acid was changed but all other variables were kept the same. The student measured the volume of carbon dioxide produced each minute for a total of 0 minutes. He did this first for the reaction between dilute sulfuric acid and a cube of calcium carbonate (limestone). The student repeated the experiment using dilute nitric acid in place of the dilute sulfuric acid. The results are shown below. (i) State two variables that must be kept the same for this investigation. Page 8 of 86

19 Reacting calcium carbonate with sulfuric acid gave different results to nitric acid. The symbol equations for the reaction of calcium carbonate with sulfuric acid and with nitric acid are shown below. CaCO 3 (s) + H SO 4 (aq) CaSO 4 (s) + H O(l) + CO (g) CaCO 3 (s) + HNO 3 (aq) Ca(NO 3 ) (aq) + H O(l) + CO (g) Describe how the results for sulfuric acid are different and use the symbol equations to explain this difference. (3) (Total 7 marks) Q. Cement is made by heating a mixture of clay and limestone in a kiln. (a) Many kilns are heated by burning natural gas (methane) in air. A chemical equation for the burning of methane is: CH 4 + O H O + CO Describe this reaction in words. Give the names of the molecules and the numbers of each molecule in this chemical equation. Page 9 of 86

20 (b) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. Limestone contains calcium carbonate. There is a large deposit of limestone under an area of natural beauty. A company wants to quarry this limestone and build a kiln near to the quarry to make cement. Area of natural beauty A quarry Evelyn Simak [CC-BY-SA-.0], via Wikimedia Commons By Thomas Bjørkan (Own work) [CC-BY-SA-3.0], via Wikimedia Commons Explosives will be used to extract the limestone out of the ground. Heavy machinery will be used to lift and crush the limestone. Lorries will be used to transport the limestone to the kiln to make cement. The lorries and the heavy machinery will use diesel fuel. Quarrying limestone and making cement will have an impact on everything near the area. Page 0 of 86

21 Describe the positive and the negative impacts of quarrying limestone and making cement (6) (Total 8 marks) Q. The amount of carbon dioxide in the Earth s atmosphere has changed since the Earth was formed. The amount of carbon dioxide continues to change because of human activities. (a) Cement is produced when a mixture of calcium carbonate and clay is heated in a rotary kiln. The fuel mixture is a hydrocarbon and air. Hydrocarbons react with oxygen to produce carbon dioxide. Calcium carbonate decomposes to produce carbon dioxide. (i) Complete each chemical equation by writing the formula of the other product. Page of 86

22 Hydrocarbons and calcium carbonate contain locked up carbon dioxide. What is locked up carbon dioxide? (b) Graph shows how the percentage of carbon dioxide in the atmosphere changed in the last 4500 million years. Use information from Graph to answer these questions. (i) Describe how the percentage of carbon dioxide has changed in the last 4500 million years. Page of 86

23 Give two reasons why the percentage of carbon dioxide has changed. (c) Graph shows how the percentage of carbon dioxide in the atmosphere changed in the last 50 years. Should we be concerned about this change in the percentage of carbon dioxide? Explain your answer (Tota 0 marks) Page 3 of 86

24 Q3. Metals are extracted from their ores. Many copper ores contain only % of copper compounds. (a) Copper is now extracted from ores containing a low percentage of copper compounds. Suggest two reasons why (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 4 of 86

25 The reaction in the furnace could cause environmental pollution. Explain how. (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. (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 5 of 86

26 Q4. The diagram shows some of the substances used and produced at a cement works. (a) Limestone is mainly calcium carbonate (CaCO 3 ). Write the correct answer in each box. (i) The formula shows that calcium carbonate (CaCO 3 ) contains different elements. () The total number of atoms in the formula CaCO 3 is. () (b) Name one of the substances produced at the cement works that causes atmospheric pollution. State one effect of this atmospheric pollution. Name... Effect Page 6 of 86

27 (c) Limestone is used to produce glass bottles. In recent years we have become more aware of the need to recycle glass bottles. Used glass bottles can be recycled if they are put into bottle banks. (i) Suggest two reasons why light bulbs should not be put into bottle banks. New glass bottles can also be produced by heating a mixture of raw materials: Suggest two environmental reasons why we should recycle glass bottles to make new glass bottles (Total 8 marks) Page 7 of 86

28 Q5. Iron is produced from the ore haematite (iron oxide). Titanium is produced from the ore rutile (titanium oxide). Iron Titanium (a) The production of low-carbon steel uses oxygen but the production of titanium uses argon. Explain why (3) Page 8 of 86

29 (b) There is less titanium than iron in the Earth s crust. Apart from titanium s scarcity, explain why titanium costs much more than iron. Use the two flow diagrams above to help you to answer this question (3) (c) Many chemical reactions take place in the production of both metals. A chemical reaction in the production of iron is: Fe O C 4 Fe + 3 CO A chemical reaction in the production of titanium is: TiCl 4 + Mg Ti + MgCl Titanium can be used to produce iron from iron oxide. The chemical reaction is: Fe O Ti 4 Fe + 3 TiO Use these three reactions and the Chemistry Data Sheet to answer this question. Suggest the position of titanium in the Reactivity Series of Metals. Explain your answer (Total 8 marks) Page 9 of 86

30 Q6. The iron produced from iron ore in a blast furnace is called cast iron. Cast iron is converted into steel in a furnace. Iron ore contains iron oxide. Coke contains carbon. (a) Quarrying iron ore will have an impact on everything near to the quarry. (i) Describe one positive impact and one negative impact of quarrying iron ore. positive impact... negative impact... Draw a ring around the correct answer to complete the sentence. carbon neutral. Ores contain enough metal to make extraction of the metal economical. reversible. () (b) Many chemical reactions take place in a blast furnace. Use the flow diagram to help you to answer this question. Suggest how the blast furnace is heated () (c) A chemical reaction for the extraction of iron is: Fe O 3 + 3CO Fe + 3CO (i) Complete the word equation for this chemical reaction carbon monoxide iron +... Page 30 of 86

31 Draw a ring around the correct answer to complete the sentence. decomposition. Iron is extracted from its ore by oxidation. reduction. () (d) Cast iron contains about 4% carbon. Cast iron is converted into low-carbon steels. (i) Low-carbon steel is produced by blowing oxygen into molten cast iron. Suggest how oxygen removes most of the carbon. Draw a ring around the correct answer to complete the sentence. corrode easily. Metals, such as nickel, are added to low-carbon steels to make the steel easy to shape. much harder. () (e) Recycling steel uses less energy than producing steel from iron ore. Tick ( ) one advantage and Tick ( ) one disadvantage of recycling steel. Statement Iron is the second most common metal in the Earth s crust. Less carbon dioxide is produced. More iron ore needs to be mined. There are different types of steel which must be sorted. Advantage Tick ( ) Disadvantage Tick ( ) (Total marks) Page 3 of 86

32 Q7. Limestone contains calcium carbonate (CaCO 3 ). (a) Name the type of reaction that takes place when calcium carbonate is heated strongly. Name the products formed (3) (b) A student investigated what happens when limestone is heated strongly. This is the method the student used: measure the mass of limestone before heating measure the mass of solid product after heating repeat the experiment three more times. The student s results are shown in the table below. Experiment Experiment Experiment 3 Experiment 4 Mass of limestone before heating in g Mass of solid product after heating in g Mass lost in g (i) Calculate the mean mass lost, taking account of any anomalies. Mean mass lost =... g Page 3 of 86

33 The student used the chemical equation to calculate the maximum mass lost by 5.0 g of calcium carbonate when heated. The maximum mass lost is. g. Suggest and explain two reasons why the mean mass lost in the experiments to heat limestone is less than. g. Do not include any reference to weighing errors in your answer. (4) (Total 9 marks) Page 33 of 86

34 Q8. Limestone is used for statues and buildings. Limestone contains calcium carbonate (CaCO 3 ). (a) Figure shows a limestone quarry. Figure Henryk Sadura/iStock/Thinkstock (i) Suggest one problem quarrying limestone will cause for people living nearby. () Suggest one benefit of quarrying limestone for people living nearby. () (iii) Why are limestone statues and buildings damaged by rain? () Page 34 of 86

35 (b) A student investigated what happens when limestone is heated, as shown in Figure. Figure This is the method the student used: measure the mass of limestone before heating measure the mass of solid product after heating repeat the experiment two more times. The student s results are shown in the table below. Experiment Experiment Experiment 3 Mass of limestone before heating in g Mass of solid product after heating in g Mass lost in g.4.6 (i) Calculate the mass lost in experiment 3. Mass lost =... g () Calculate the mean mass lost in the three experiments. Mean mass lost =... g () (iii) Suggest one reason why the mass lost was not the same for the three experiments. () Page 35 of 86

36 (c) The word equation for the reaction when calcium carbonate is heated is: calcium carbonate calcium oxide + carbon dioxide (i) Complete the sentence. The reaction when calcium carbonate is heated is called thermal.... () Heating 5.0 g of calcium carbonate produces.8 g of calcium oxide. Calculate the mass of carbon dioxide produced. Mass of carbon dioxide =... g () (iii) Describe how to test a gas to show that it is carbon dioxide. Test... Result... (Total 0 marks) Page 36 of 86

37 Q9. This question is about metals. Figure shows the metals used to make pylons and the wires of overhead cables. (a) An ore contains a metal compound. A metal is extracted from its ore in three main stages, as shown in Figure. Explain why Stage needs to be done Page 37 of 86

38 (b) Cast iron from a blast furnace contains 96% iron and 4% carbon. (i) Cast iron is not suitable for the manufacture of pylons. Give one reason why. () Most cast iron is converted into steel, as shown in Figure 3. Describe how cast iron is converted into steel. Use Figure 3 to help you to answer this question. (c) Aluminium and copper are good conductors of electricity. (i) State one property that makes aluminium more suitable than copper for overhead cables. () How can you tell that copper is a transition metal and aluminium is not a transition metal from the position of each metal in the periodic table? Page 38 of 86

39 (iii) Copper can be extracted from solutions of copper salts by adding iron. Explain why. (Total 0 marks) Q0. Limestone is used to make many different materials. (a) Heating limestone produces calcium oxide and carbon dioxide. Complete the sentences. (i) The main compound in limestone is calcium.... () The reaction to produce calcium oxide from limestone is thermal.... () (iii) Calcium hydroxide is produced when calcium oxide reacts with.... () (iv) Calcium hydroxide is used to neutralise acids because it is an.... () Page 39 of 86

40 (b) Cement is made from limestone and clay. Concrete is made by mixing cement with water, sand and aggregate (small pieces of rock). A group of students did an investigation on the amount of aggregate needed to make the strongest concrete beam. The students used this method: use the same mass of cement and the same mass of sand but change the mass of aggregate to make seven different concrete mixtures use the different concrete mixtures to make beams of the same size add weights, as shown in Figure, until the concrete beam breaks. The students results are plotted on the graph in Figure. (i) One of the points is anomalous. Complete the graph in Figure by drawing two straight lines of best fit. Page 40 of 86

41 Describe one way the students could improve the method so that their results are more accurate for each graph point. (iii) What force is needed to break a concrete beam containing no aggregate? Show your working on the graph. Force =... newtons (iv) One of the students concluded that: The force needed to break a concrete beam increases as the mass of aggregate increases. The student s conclusion is not completely correct. Use values from the graph to explain why. (3) (Total 3 marks) Page 4 of 86

42 Q. The picture shows a limestone quarry. By Thomas Bjørkan (Own work) [CC-BY-SA-3.0], via Wikimedia Commons (a) Local residents were against the opening of a new limestone quarry. The quarry was estimated to have a 0-year operating period. The quarry company gave reasons to show how the quarry could benefit local residents over the next 0 to 5 years. Suggest one economic and one environmental reason the quarry company could give. Economic reason Environmental reason (b) What happens when limestone (calcium carbonate) is heated? Include in your answer: the chemical names of the substances produced the name of the process Page 4 of 86

43 (c) (i) Lime is calcium oxide. Calcium oxide reacts with water to form calcium hydroxide, Ca(OH) Write the symbol equation for this reaction Name the gas that a solution of calcium hydroxide in water is used to test for. Give the result that you would see if the gas was present (Total 8 marks) Page 43 of 86

44 Q. Limestone is a rock. Many buildings and statues are made from limestone. The picture shows a limestone quarry. By Thomas Bjørkan (Own work) [CC-BY-SA-3.0], via Wikimedia Commons (a) A company wants to open a limestone quarry. (i) Some local people want the quarry to be opened. Suggest one reason why () Other local people do not want the quarry to be opened. Suggest one reason why () (b) Limestone is used to produce other materials. Draw a ring around the correct answer in each box to complete each sentence. CaCO 3 (i) Limestone is mainly made of CuCO 3 ZnCO 3 () Page 44 of 86

45 When limestone is heated it forms a metal oxide and a gas. carbon dioxide. The gas is carbon monoxide. oxygen. () combustion. (iii) This type of reaction is called decomposition. oxidation. () (Total 5 marks) Q3. (a) Describe how a student could test for carbon dioxide. Give the result of the test (b) Many useful materials are obtained from limestone. Cement is made from limestone. Complete the sentence. Cement is made by heating limestone with.... () Page 45 of 86

46 (c) Concrete contains cement. A student tested four concrete slabs. The student dropped a steel ball onto the concrete slabs. The concrete slabs were of equal thickness. The concrete slabs contained different amounts of fibre. The student dropped the steel ball from increasing heights until the concrete cracked. The results are shown on the graph. (i) Which property of the concrete slabs did the student test? Give one factor that the student kept constant during the investigation () (iii) What was the minimum height the steel ball was dropped from to crack concrete containing 0 % fibre? Height =... cm () Page 46 of 86

47 (iv) Give a conclusion for the student s investigation. () (d) Calcium hydroxide is an important substance used in the agricultural industry (i) Calcium hydroxide is made from limestone (calcium carbonate) in a two-stage process. Complete the word equations which describe the two stages. Stage calcium carbonate calcium oxide +... Stage calcium oxide +... calcium hydroxide Calcium hydroxide is an alkali. It is used by farmers to spread on fields where the soil is acidic. Suggest why farmers use calcium hydroxide in this way. () (Total 0 marks) Page 47 of 86

48 Q4. A student investigated heating metal carbonates. The student used the apparatus in the figure below. The student s results are shown in the table below. Metal carbonate Colour before heating Colour after heating Mass before heating in g Mass after heating in g Limewater Copper carbonate Potassium carbonate Zinc carbonate Green Black White White 3.8 White White.5 8. Turns cloudy (a) Explain the observations seen when heating copper carbonate. Include the names of the substances produced (3) (b) (i) Potassium carbonate did not decompose when heated. State why. () Page 48 of 86

49 Complete the table above to show the results you would expect the student to obtain. (3) (Total 7 marks) Q5. A student investigated heating metal carbonates. The student used the apparatus in the figure below. The student s results are shown in the table below. Metal carbonate Colour before heating Colour after heating Mass before heating in g Mass after heating in g Solution A Copper carbonate Potassium carbonate Zinc carbonate Green Black White White White White.5 8. Turns cloudy Stays colourless Turns cloudy (a) Use the correct answer from the box to complete the sentence. black green white The colour of copper oxide is.... () (b) Solution A is used to test for carbon dioxide. Carbon dioxide turns Solution A cloudy. What is the name of Solution A?... () Page 49 of 86

50 (c) (i) Use the correct answer from the box to complete the sentence. neutralisation purification decomposition Most metal carbonates produce the metal oxide and carbon dioxide when heated. The reaction taking place is called.... () Potassium carbonate did not react. How can you tell from the information in the table above that potassium carbonate did not react? Give three reasons for your answer (3) (Total 6 marks) Page 50 of 86

51 Q6. Figure shows a limestone building. Limestone buildings are damaged by substances in the air. Figure Fontanis/iStock (a) Complete the following sentences. Sulfur dioxide in the air affects limestone buildings. This is because sulfur dioxide is a cause of... rain which reacts with limestone. Limestone is mainly composed of the compound... carbonate. Page 5 of 86

52 (b) Figure shows the concentration of sulfur dioxide in the air from 980 to 00. Figure (i) Describe the trend shown in Figure. Year () All petrol now sold in the UK is sulfur-free. Suggest two reasons why. (Total 5 marks) Q7. Limestone is mainly calcium carbonate. (a) Limestone is used to make cement. What is added to limestone to make cement? Draw a ring around the correct answer. aggregate clay mortar sand () Page 5 of 86

53 (b) Manufacturing cement from 000 kg of limestone produces a total of 800 kg of carbon dioxide. One of the reactions in manufacturing cement is the thermal decomposition of calcium carbonate. The equation shows what happens when 000 kg of calcium carbonate decomposes to form 560 kg of calcium oxide at 500 C. CaCO 3 CaO + CO (i) How much carbon dioxide is produced when 000 kg of calcium carbonate is completely decomposed? () Suggest why the total amount of carbon dioxide produced by the manufacturing process is greater than your answer to part (i). () Page 53 of 86

54 (c) Cement and sand are used to make concrete. A student made some kg concrete blocks. The student varied the percentage of cement in the mixture. The student tested the strength of the concrete blocks by hanging masses from the block, as shown in Figure, until the block broke. Figure shows the student s results. Give two conclusions that can be made from these results (Total 5 marks) Page 54 of 86

55 Q8. Limestone is used to make cement. (a) When cement is made, limestone is strongly heated. Limestone is mainly calcium carbonate. The equation shows what happens when 500 kg of calcium carbonate (CaCO 3 ) is strongly heated. CaCO 3 CaO + CO 500 kg 80 kg (i) What is the chemical name of CaO? () What is the mass of carbon dioxide (CO ) produced in this reaction? Draw a ring around the correct answer. 0 kg 500 kg 780 kg () (b) Which of these building materials is made when cement is mixed with sand? Draw a ring around the correct answer. clay mortar stone () Page 55 of 86

56 (c) Cement is used to make concrete. A student investigated the strength of kg concrete blocks. The student used different masses of cement to make each concrete block. The diagram shows the apparatus the student used to test the strength of the kg concrete blocks. The student tested each concrete block by adding masses until the block broke. The student s results are shown below in the table. Mass of cement in g Mass needed to break the block in kg (i) Give two conclusions using the data from the table above. Page 56 of 86

57 Suggest one way the student could improve the investigation. () (Total 6 marks) Page 57 of 86

58 M. (a) (i) (thermal) decomposition allow it breaks down accept symbol equation or in words allow reaction with SO (to form CO ) calcium carbonate / calcium oxide / limestone / quicklime / it reacts with sulfur dioxide / forms calcium sulfate accept it neutralises sulfur dioxide / neutralisation ignore references to sulfur do not accept calcium reacts with... (b) by incomplete / partial combustion (of the fuel) insufficient oxygen / air (to burn fuel) accept insufficient oxygen / air to burn fuel completely for marks if no other marks awarded accept C + CO CO or C + O CO or in words for mark (c) (i) any two from: (CO ) from the atmosphere (CO ) taken in millions of years ago or early (atmosphere) allow thousands / billions allow rocks formed millions of years ago (CO ) was used to form the shells / skeletons of marine organisms / fossil fuels accept sedimentary rocks allow used to form correct named fossil fuel ignore limestone Page 58 of 86

59 any one from: (increases / enhances) global warming allow greenhouse gas / effect do not accept ozone layer / acid rain / global dimming ignore consequences of global warming is additional carbon dioxide or not able to be absorbed by oceans / seas or used by (green) plants acidification of sea water [7] M. (a) building (b) provides jobs (c) any two from: ignore references to water noise allow sound pollution dust / visual pollution accept global dimming ignore smoke air / atmospheric exhaust gases accept acid rain / global warming / named gaseous pollutants (more) traffic accept more lorries (d) O ignore any numbers 3 / three Page 59 of 86

60 (e) calcium oxide accept quicklime do not accept calcium dioxide [7] M3. (a) gas / carbon dioxide / CO (produced / released) ignore how gas is formed (b) any two from: calcium oxide / CaO / quicklime (is the solid) (calcium oxide) reacts with water accept reacts to form calcium hydroxide / calcium carbonate or carbon dioxide argon would not react Page 60 of 86

61 (c) for full marks: candidates should consider and explain four of the following points: for full marks candidates must have at least one advantage and one disadvantage allow only one advantage / disadvantage for each point but each point could be correctly explained as an advantage and a disadvantage for marks ignore issues common to all sites eg scarring the landscape / area of natural beauty ignore comments about sites other than the one chosen unless a comparison is made Wood / habitats screening / use of wood damage to habitat Town (proximity) - noise / visual / dust pollution / damage / subsidence ignore pollution unless explained 3 Labour force- proximity to site (travelling time / use of fuel / carbon footprint) 4 River - pollution due to nearness 5 Transport (of materials) (nearness to road / railway) 6 Quality of limestone - (best D C A B worst) amount of waste 7 Wind direction carries dust, noise, fumes etc towards town (only B & D are directly downwind of town) 4 [7] M4. (a) (i) 3 / three nitrogen does not react allow nitrogen is not used up in the reaction Page 6 of 86

62 carbon dioxide is a product of methane / fuel burning / reacting with oxygen accept oxygen in the air reacts with methane carbon dioxide is a product of calcium carbonate decomposing (to produce calcium oxide) do not allow calcium carbonate reacts with oxygen (b) any two from: water and calcium oxide / quicklime react ignore mix to produce calcium hydroxide / slaked lime energy / heat released / exothermic ignore gets hot/heats up correct word equation = marks [6] M5. (a) / one 3 / three (b) (i) air linked to nitrogen and oxygen quicklime linked to calcium oxide waste gases linked to nitrogen and carbon dioxide mixture burns / combusts accept methane reacts with air / oxygen accept as a fuel to provide energy / heat (c) as a building material to make cement [9] Page 6 of 86

63 M6. (a) (i) water accept hydrogen oxide allow H O carbon dioxide allow CO accept any soluble carbonate or carbonic acid (b) (i) CaCO 3 + HCl CaCl + CO + H O because sulfur reacts with oxygen / air to produce sulfur dioxide or sulfur burns to produce sulfur dioxide accept correct equation and (sulfur dioxide) causes acid rain that reacts with/erodes limestone/ calcium carbonate ignore wears away (c) (i) it = carbon dioxide ignore references to carbon dioxide is in the air because carbon dioxide is produced from burning methane accept correct equation because carbon dioxide is produced from decomposing calcium carbonate/limestone accept correct equation do not accept carbon in calcium carbonate reacting with air nitrogen this is the main gas / 75 80% / of air allow there is a lot of this gas in air [9] M7. (a) (i) react allow neutralise allow bubbles / fizzes accept produces gas / CO F ignore rises Page 63 of 86

64 stop reacting / producing stops on its own is insufficient allow stop working / bubbling / fizzing (iii) the (hydrochloric) acid / (calcium) carbonate is used up accept because the (calcium) carbonate has neutralised the (hydrochloric) acid OR have been used up () the graph line becomes horizontal / levels out () OR stays the same / no change () ignore reference to graph line no further reaction () bubble the gas through limewater / calcium hydroxide solution allow (add) limewater test must be correct to gain result mark (the solution) goes cloudy allow milky (b) advantage > Quarrying limestone provides building materials, employment and new road links disadvantage > Quarrying limestone releases dust, and lorries release carbon dioxide from burning diesel fuel [7] M8. (a).5 correct answer with or without working gains marks if answer incorrect.6 /.65 /.6 /.63 or recognise 3.0 as anomalous gains mark accept answer in table ignore units Page 64 of 86

65 (b) as the percentage of cement increases the mass needed to break the sleeper increases allow 50% cement is the strongest or 30% sand is the strongest or the highest amount of cement is the strongest or as the percentage of sand increases the mass needed to break the sleeper decreases (c) (i) any two from: availability of materials cost (of materials) time needed (for the concrete mixture) to set/harden compression strength (of the concrete) accept weight of the train testing full size (concrete railway sleepers) accept any test on full size sleepers accept how well it would last / weather Page 65 of 86

66 any four from: maximum of 3 marks if no comparison made ignore yes or no negative concrete: allow converse statements for wood more fossil fuel / energy / heat (needed to produce cement / concrete) cement / concrete resources / limestone not renewable whereas wood is renewable quarrying limestone destroys landscapes / habitats whereas growing wood improves landscapes / habitats allow quarrying causes noise pollution / dust / etc. making cement / concrete releases carbon dioxide / greenhouse gases whereas growing wood absorbs carbon dioxide / greenhouse gases / is carbon neutral allow making cement / concrete causes global warming / climate change whereas growing wood reduces global warming / climate change ignore loss of trees / deforestation (and resultant effects such as an increase in CO ) positive concrete: (less resources are needed because) cement / concrete sleepers last longer or wood rots / needs replacing ignore strength / ease of breaking ignore weathering / effects of acid rain 4 [9] M9. (a) (i).5(kg) ignore units 40% (cement) and Test 3 ignore units because it is anomalous or because it is much lower than the other two readings accept value not used to calculate mean ignore outlier Page 66 of 86

67 (iii) (iv) as the percentage of cement increases the mass needed to break the sleeper increases allow strength for mass needed allow correct relationship using percentage of sand volume/percentage / amount of water accept temperature (b) any two from: availability (of the raw materials) cost of the raw materials purity (of the raw materials) [7] M0. (a) limewater or calcium hydroxide solution (reacts with carbon dioxide and) turns cloudy / milky linked to first point if no other mark awarded puts out lighted splint gains mark (b) (i) any two from: same volume / amount of the acids concentration of the acids temperature same surface area / size / mass / amount of calcium carbonate same measuring equipment Page 67 of 86

68 any three from: (after about 4 minutes) the sulfuric acid stops reacting or nitric acid continues to react accept more CO with nitric acid at any time after 4 minutes (initially) the reaction with sulfuric acid is faster (the reaction stops) because calcium sulfate is a solid allow sulfuric acid produces a solid (the reaction continues) because calcium nitrate is soluble / in solution / aqueous allow nitric acid produces an (aqueous) solution because the calcium sulfate prevents the sulfuric acid reacting with the calcium carbonate (the rate is faster) because sulfuric acid contains two hydrogens 3 [7] M. (a) one / (molecule of) methane (reacts with) two / (molecules of) oxygen two / (molecules of) water / steam / hydrogen oxide and one / (molecule of) carbon dioxide (are produced) if no other marks awarded all four names correct or correct number and name for two molecules or 4 correct numbers gains mark allow all four names correct and correct number of atoms in each substance for marks Page 68 of 86

69 (b) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Examiners should also apply a best-fit approach to the marking. 0 marks No relevant content Level (- marks) There is a simple description of a positive and / or a negative impact caused by the plan to quarry limestone and / or make cement. Level (3-4 marks) There is a clear description of both a positive and a negative impact caused by the plan to quarry limestone and / or make cement. Level 3 (5-6 marks) There is a detailed description of both positive impacts and negative impacts caused by the plan to quarry limestone and / or make cement. examples of the chemistry points made in the response Positive impacts: Limestone / cement is used for building Limestone needed for industrial processes Company landscapes / provides recreation facilities in the quarry after use Provides employment Improves local economy Improved transport links Negative impacts: Destruction of habitats Fewer plants / trees to absorb carbon dioxide Example of visual pollution Example of noise pollution Example of atmospheric pollution More traffic 6 [8] M. (a) (i) H O must be formula Page 69 of 86

70 CaO must be formula carbon dioxide from the air / (Earth s early) atmosphere it = carbon (dioxide) accept carbon dioxide from millions of years ago formed (sedimentary) rocks or fossil fuels ignore trapped / stored (b) (i) decreases rapidly at first it = carbon (dioxide) then slowly or levels off allow both marks if the description is correct using either rapidly or slowly allow correct use of figures for either marking point if no other mark awarded, allow CO decreased for mark any two from: it = carbon (dioxide) accept photosynthesis used by plants dissolved in oceans locked up in fossil fuels or formed fossil fuels locked up in rocks or formed rocks (c) (yes) it = percentage of carbon (dioxide) ignore yes or no because the percentage of carbon dioxide is increasing which causes global warming (to increase) allow (carbon dioxide) causes greenhouse effect/climate change Page 70 of 86

71 or (no) because the percentage of carbon dioxide is low () compared to millions of years ago () allow global warming can be caused by other factors (e.g. Sun / water vapour / methane) [0] M3. (a) any two from: copper / ores are running out / harder to find there are no / very small amounts of high-grade copper ores left copper metal is in demand copper is expensive now economical to extract copper from low-grade ores it = copper allow new methods of extraction e.g. bioleaching and phytomining allow high-grade ores are running out for marks (b) (i) large amounts / 98% of rock to dispose of as waste accept contains toxic (metal) compounds / bioleacher or waste rock takes up a lot of space (copper sulfide reacts with oxygen to) produce sulfur dioxide / SO allow (sulfur reacts with oxygen to) produce sulfur dioxide / SO that causes acid rain allow description of effects of acid rain or sulfur dioxide if no other mark awarded allow CO produced which causes global warming or CO produced by burning fuel or heating the furnace for mark Page 7 of 86

72 (iii) any one from: large amounts of fuels / energy used (for the furnace and electrolysis) allow large amounts of electricity needed ignore high temperature / electrolysis unqualified (the extraction has) many steps / stages / processes allow (extraction) is a long process / takes a lot of time large amounts of ore / material have to be mined allow ores contain a low percentage of copper (iv) (copper ions move towards) the negative electrode / cathode because copper ions / Cu + are positively charged or are oppositely charged or copper ions need to gain electrons allow because metal ions are positive or opposites attract (v) (growing) plants [9] M4. (a) (i) 3 / three 5 / five (b) carbon dioxide / CO for a correct emission (causes) global warming / climate change / greenhouse gas explanation must be correct for named emission ignore ozone layer or (cement) particles / smoke () (causes) asthma / dust / (global) dimming () accept breathing problems or sulfur dioxide / SO / nitrogen oxides / NO x () (causes) acid rain () do not accept nitrogen or water vapour for emissions do not accept no named emission Page 7 of 86

73 (c) (i) any two from: ignore contamination without explanation contain metals/ filaments / wires accept named metal(s) contain other / toxic chemicals / materials accept named chemical(s) / material(s) different type of glass accept glass would not metl ignore thicker / thinner glass any two from: allow converse arguments low / less energy / heat or lower temperature needed ignore no energy without explanation low / less fuel burned ignore no fuel without explanation accept less fuel for extraction / transportation of raw materials no / less carbon dioxide / global warming / less use of carbonate(s) accept name(s) of this carbonate(s) less landfill ignore less litter less use of resources / raw materials [8] M5. (a) (because to produce low-carbon steel) oxygen is needed to react with / oxidise carbon accept (to produce low-carbon steel) oxygen removes carbon as carbon dioxide (to produce titanium) an atmosphere of argon is used because it is unreactive any oxygen / air would react with / oxidise magnesium or titanium ignore magnesium chloride / titanium chloride reacts with oxygen Page 73 of 86

74 (b) for titanium: it = titanium ignore references to abundance / usefulness / temperature / amounts / relative reactivity / equipment allow converse arguments for iron there are more stages in its manufacture accept slower rate of production or is more labour intensive or a batch process is used or the process used is not continuous larger amounts of energy are needed accept the titanium chloride is cooled and reheated which is not energy efficient (c) magnesium / chlorine / argon have to be produced or are expensive or are used titanium is below magnesium and above iron (in the reactivity series of metals) allow similar position to aluminium or carbon or zinc because magnesium removes chlorine from titanium chloride and titanium removes oxygen from iron oxide allow magnesium displaces titanium and titanium displaces iron OR magnesium more reactive than titanium because it removes chlorine from titanium chloride () accept magnesium more reactive than titanium because it displaces titanium titanium more reactive than iron because it removes oxygen from iron oxide () accept titanium more reactive than iron because it displaces iron [8] M6. (a) (i) Positive impact any one from: provides employment or improves local economy improved transport - new roads are built, new rail links after use the quarry could provide recreation facilities Page 74 of 86

75 Negative impact any one from: destruction of animal habitats fewer plants and trees to absorb carbon dioxide visual pollution or noise pollution or atmospheric / air pollution allow dust pollution more traffic uses non-renewable resources allow pollutants from burning diesel economical (b) carbon / coke burns (in oxygen / air) accept carbon / coke reacts with oxygen / air (c) (i) iron oxide (reactant) must be words carbon dioxide (product) reduction (d) (i) oxygen reacts with carbon or oxygen and carbon produce carbon dioxide / carbon monoxide carbon dioxide / carbon monoxide is a gas or the carbon is removed as a gas much harder (e) Advantage: less carbon dioxide is produced Page 75 of 86

76 Disadvantage: there are different types of steel which must be sorted [] M7. (a) (thermal) decomposition accept limestone decomposes allow endothermic (to produce) calcium oxide / CaO or quicklime (to produce) carbon dioxide / CO accept a correct word or chemical equation for the last two marking points (b) (i).8(g) accept correct answer with or without working accept for mark if no other mark awarded allow mark for.6(g) or any calculation with one error the limestone was not pure (calcium carbonate) or contained impurities so less carbon dioxide was produced the temperature was not high enough allow not heated for long enough so the limestone / calcium carbonate did not fully decompose / react [9] M8. (a) (i) any one from: destruction of habitats fewer plants / trees to absorb carbon dioxide dust / noise / air / visual (pollution) allow breathing problems more traffic Page 76 of 86