Reactivity series — Paper 3 · IGCSE Science - Combined 0653

8 Fig. 8.1 shows some uses of copper. coin pipe wire Fig. 8.1 Copper is extracted from copper oxide by reacting it with carbon. The word equation for this reaction is: copper oxide + carbon copper + carbon dioxide (a) (i) Name the collection of metals in the Periodic Table which includes copper. … [1] (ii) Use the word equation to identify the substance which is being reduced during the extraction of copper from copper oxide. … [1] (iii) A hairdryer is powered through a cable containing copper wire. Copper is a good conductor of electricity. State one other property of copper that makes it a suitable material for use in a power cable. … [1] (iv) Suggest one reason why copper, rather than iron, is used to make water pipes. … [1] (v) Explain why copper alloys, rather than pure copper, are used to make coins. … [1] (b) Three metals are placed into beakers of dilute hydrochloric acid, as shown in Fig. 8.2. iron magnesium zinc dilute hydrochloric acid Fig. 8.2 State which of the three metals in Fig. 8.2 reacts most rapidly with dilute hydrochloric acid. Name the gas which is made when this metal reacts with dilute hydrochloric acid. metal … gas … [2]

7 marks

Mark scheme: 8(a)(i) transition ; 1 8(a)(ii) copper oxide / CuO ; 1 8(a)(iii) ductile / high melting point ; 1 8(a)(iv) Iron / Fe is too reactive / reacts / rusts (with water) / copper is less reactive (than iron); 1 8(a)(v) stronger / does not get damaged ; 1 8(b) (metal) magnesium ; (gas) hydrogen ; 2

This question in 0653/31 May/June 2017

2 (a) A teacher places the first three metals of Group I in the Periodic Table into separate beakers of water. This is shown in Fig. 2.1. water beaker A beaker B beaker C Fig. 2.1 The three pieces of metal are the same size. A student records her observations in Table 2.1. Table 2.1 time for metal beaker the metal floats the metal melts to fully react in flames are seen seconds A yes yes 15 yes B yes no 60 no C yes yes 40 no (i) Use the information in Table 2.1 to identify the three metals in beakers A, B and C. beaker A … beaker B … beaker C … [2] (ii) Name the gas produced when Group I metals react with water. … [1] (iii) When the metals have completely reacted, the teacher places pieces of red litmus paper and blue litmus paper into each beaker. Describe the changes, if any, that are seen. red litmus paper … blue litmus paper … [1] (b) The student places pieces of copper, iron, magnesium and zinc into dilute hydrochloric acid. (i) State which of the four metals react fastest. … [1] (ii) State which of the four metals does not react at all. … [1] (iii) Suggest why Group I metals must not be added to dilute hydrochloric acid. … … [1] (c) Saucepans are usually made from an iron alloy rather than from pure iron. Some coins are made from a copper alloy rather than from pure copper. Explain why these alloys are used instead of the pure metals. (i) iron alloy for saucepans … … [1] (ii) copper alloy for coins … … [1]

9 marks

Mark scheme: 2(a)(i) potassium / K lithium / Li sodium / Na ;; 2 2(a)(ii) hydrogen / H2 ; 1 2(a)(iii) turns blue and stays blue / no change ; 1 2(b)(i) magnesium / Mg ; 1 2(b)(ii) copper / Cu ; 1 2(b)(iii) (too) dangerous / (risk of) explosion ; 1 2(c)(i) resists corrosion / does not rust ; 1 2(c)(ii) stronger / does not get damaged ; 1

This question in 0653/32 May/June 2017

2 (a) A teacher places the first three metals of Group I in the Periodic Table into separate beakers of water. This is shown in Fig. 2.1. water beaker A beaker B beaker C Fig. 2.1 The three pieces of metal are the same size. A student records her observations in Table 2.1. Table 2.1 time for metal beaker the metal floats the metal melts to fully react in flames are seen seconds A yes yes 15 yes B yes no 60 no C yes yes 40 no (i) Use the information in Table 2.1 to identify the three metals in beakers A, B and C. beaker A … beaker B … beaker C … [2] (ii) Name the gas produced when Group I metals react with water. … [1] (iii) When the metals have completely reacted, the teacher places pieces of red litmus paper and blue litmus paper into each beaker. Describe the changes, if any, that are seen. red litmus paper … blue litmus paper … [1] (b) The student places pieces of copper, iron, magnesium and zinc into dilute hydrochloric acid. (i) State which of the four metals react fastest. … [1] (ii) State which of the four metals does not react at all. … [1] (iii) Suggest why Group I metals must not be added to dilute hydrochloric acid. … … [1] (c) Saucepans are usually made from an iron alloy rather than from pure iron. Some coins are made from a copper alloy rather than from pure copper. Explain why these alloys are used instead of the pure metals. (i) iron alloy for saucepans … … [1] (ii) copper alloy for coins … … [1]

9 marks

Mark scheme: 2(a)(i) potassium / K lithium / Li sodium / Na ;; 2 2(a)(ii) hydrogen / H2 ; 1 2(a)(iii) turns blue and stays blue / no change ; 1 2(b)(i) magnesium / Mg ; 1 2(b)(ii) copper / Cu ; 1 2(b)(iii) (too) dangerous / (risk of) explosion ; 1 2(c)(i) resists corrosion / does not rust ; 1 2(c)(ii) stronger / does not get damaged ; 1

This question in 0653/33 May/June 2017

2 A student places four pieces of metal, at the same time, into separate beakers containing dilute hydrochloric acid, HCl. The four metals react with the acid to produce the same gas, but at different rates. The gas is collected in test-tubes, as shown in Fig. 2.1. gas bubbles of gas dilute metalhydrochloric acid metal A metal B metal C metal D Fig. 2.1 The four metals are calcium, iron, magnesium, and zinc. (a) (i) Using the information in Fig. 2.1 and your knowledge of the reactivity series, identify metals A, B, C and D. metal A … metal B … metal C … metal D … [2] (ii) Name the gas made in the reaction between magnesium and dilute hydrochloric acid. … [1] (iii) State the effect of increasing the temperature of the acid on the rate of reaction with the metals. … [1] (iv) Suggest one other way of changing the rate of reaction. … [1] (b) When iron reacts with dilute hydrochloric acid, a solution of an iron salt is made. The student thinks that this salt contains iron(II) ions. Another student thinks that the salt contains iron(III) ions. They add dilute sodium hydroxide solution to a sample of the iron salt solution. Describe the observations that are expected for iron(II) ions and for iron(III) ions. iron(II) ions … iron(III) ions … [2] (c) Iron is a transition metal. (i) Suggest two properties of iron that are not properties of Group I metals. 1. … 2. … [2] (ii) Explain why iron is used in the form of alloys, rather than as pure iron, for kitchen knives. … … … [1]

10 marks

Mark scheme: 2(a)(i) (metal A) calcium / Ca (metal B) magnesium / Mg (metal C) zinc / Zn (metal D) iron / Fe ;; 2 2(a)(ii) hydrogen ; 1 2(a)(iii) increases (rate) ; 1 2(a)(iv) any one from change / increase / decrease concentration / surface area / (solid) particle size ; use / add a catalyst ; max 1 2(b) (iron(II) ions) green ppt / solid ; (iron(III) ions) brown ppt / solid ; 2 2(c)(i) Any two from high_density ; high_melting point ; (form) coloured compounds ; catalysts ; 2 Question Answer Marks 2(c)(ii) (alloys are) harder / more resistant to wear / more resistant to corrosion ; 1

This question in 0653/32 Oct/Nov 2017

8 (a) Molten lead(II) bromide is broken down into simpler substances using the apparatus shown in Fig. 8.1. low voltage d.c.supply … … – + molten lead (II) bromide Fig. 8.1 (i) Use the names of the electrodes to complete Fig. 8.1. [2] (ii) Describe the appearance of the substance that forms at the positive electrode. … [1] (b) Copper is extracted from copper oxide by heating with carbon. The equation for this reaction is copper oxide + carbon copper + carbon dioxide. State whether the copper oxide is oxidised or reduced during this reaction. Explain your answer. … … [1] (c) Copper, Cu, does not react with water. Calcium, Ca, reacts rapidly with water. Magnesium, Mg, reacts slowly with water. Potassium, K, reacts very rapidly with water. Place these four metals in order of reactivity, from most to least reactive. … most reactive … … … least reactive [2] (d) A student adds excess magnesium to dilute hydrochloric acid. (i) State two changes that the student can make to increase the rate of this reaction. 1. … 2. … [2] (ii) Identify the salt produced during this reaction. … [1] (iii) After the reaction finishes, the student removes the unreacted magnesium from the solution that has formed. Name the separation technique that the student uses. … [1]

10 marks

Mark scheme: 8(a)(i) (left) cathode ; (right) anode ; 2 8(a)(ii) orange / brown gas ; 1 8(b) (reduced) oxygen is removed ; 1 8(c) K Ca Mg Cu ;; 2 8(d)(i) any two from heat / increase temperature ; increase surface area of magnesium ; increase concentration of acid ; use / add a catalyst ; 2 8(d)(ii) magnesium chloride ; 1 8(d)(iii) filter / filtration ; 1

This question in 0653/33 Oct/Nov 2017

2 (a) A student investigates the reactivity of four different metals. She places pieces of calcium, copper, iron and zinc separately in dilute hydrochloric acid, as shown in Fig. 2.1. metal dilute hydrochloric acid Fig. 2.1 (i) Place these four metals in order of reactivity, from most to least reactive. … most reactive … … … least reactive [2] (ii) Suggest what happens to the pH number of the acid when it reacts with a piece of metal. … [1] (b) Excess magnesium powder reacts with dilute hydrochloric acid. During this reaction, a gas and aqueous magnesium chloride solution are produced. (i) Name this gas. … [1] (ii) State how the unreacted solid magnesium can be removed from the reaction mixture. … [1] (iii) State how solid magnesium chloride can be obtained from magnesium chloride solution. … [1] (c) An atom of an isotope of magnesium is represented by: 2512Mg (i) State the atomic number and the mass number of this atom. atomic number … mass number … [1] (ii) State the number of neutrons in this atom. … [1] (d) Aluminium is used in overhead power cables. Aluminium alloys are used in aircraft bodies. (i) State the physical property of aluminium that makes it suitable for use in power cables. … [1] (ii) Explain why aluminium alloys, rather than pure aluminium, are used in aircraft bodies. … [1]

10 marks

Mark scheme: 2(a)(i) calcium Ca zinc / Zn iron / Fe copper / Cu ;; 1 mark for calcium first and copper last 2 marks for all four correct 2 2(a)(ii) increases / goes up / gets (closer) to 7 ; 1 2(b)(i) hydrogen ; 1 2(b)(ii) filter / filtering / filtration ; 1 2(b)(iii) crystallisation / evaporation / heat ; 1 2(c)(i) (atomic no.) 12 and (mass no.) 25 ; 1 2(c)(ii) 13 ; 1 2(d)(i) (electrical) conductor ; 1 2(d)(ii) higher strength ; 1

This question in 0653/31 May/June 2018

5 (a) A student investigates the rate of reaction of four metals, calcium, iron, magnesium and zinc, with dilute hydrochloric acid. She uses pieces of metal which are all of the same size. A gas is produced when the metals react. She uses the apparatus shown in Fig. 5.1. measuring cylinder gas dilute hydrochloric acid piece of metal Fig. 5.1 The student determines the rate of the reaction between each metal and the dilute acid. (i) Describe the two measurements that the student records for each reaction. 1. … 2. … [2] (ii) Place calcium, iron, magnesium and zinc, in order of rate of reaction, from highest to lowest. … highest … … … lowest [1] (iii) During the reaction between magnesium and dilute hydrochloric acid, hydrogen gas and a salt are produced. Complete the word equation for this reaction. magnesium + + [2] (iv) Describe a test for hydrogen gas. State the test result. test … result … … [2] (b) Copper is a metal which is extracted by heating copper oxide with carbon. The equation for this reaction is: copper oxide + carbon copper + carbon dioxide Name the substance that is oxidised during this reaction. Explain your answer. substance … explanation … … [1]

8 marks

Mark scheme: 5(a)(i) time taken ; volume of gas ; 2 5(a)(ii) (highest) calcium / Ca magnesium / Mg zinc / Zn (lowest) iron / Fe 1 5(a)(iii) (magnesium) + hydrochloric acid Î hydrogen + magnesium chloride magnesium chloride identified anywhere ; all species correct and in correct places ; 2 5(a)(iv) (test) lighted splint ; (result) burns with a (squeaky) ‘pop’ ; 2 5(b) (substance) carbon and (explanation) gains oxygen / O ; 1

This question in 0653/33 Oct/Nov 2018

5 A student investigates the reactivities of four metals, calcium, magnesium, tin and zinc. She reacts 1 g pieces of each metal separately with excess dilute hydrochloric acid. She collects and measures the gas from each reaction using a measuring cylinder, as shown in Fig. 5.1. gas measuring cylinder excess dilute hydrochloric acid metal Fig. 5.1 The time taken to collect 20 cm3 of gas in each experiment is recorded in Table 5.1. Table 5.1 metal time taken / s calcium 20 magnesium 55 tin more than 300 zinc 100 (a) (i) Deduce the order of reactivity of the four metals, calcium, magnesium, tin and zinc, from most reactive to least reactive. … most reactive … … … least reactive [2] (ii) Suggest two changes that can be made to increase the rate of reaction of a metal with hydrochloric acid. 1. … 2. … [2] (b) (i) Identify the gas produced when zinc reacts with dilute hydrochloric acid. … [1] (ii) Fig. 5.2 shows some gases and tests for gases. The boxes on the left show the gases. The boxes on the right show the tests. gas test ammonia glowing splint carbon dioxide damp red litmus paper oxygen limewater Fig. 5.2 On Fig. 5.2 draw one line from each gas to the test used for the gas. [2] (c) The four metals, calcium, magnesium, tin and zinc, have high melting points and high boiling points. Suggest two other physical properties of these metals. 1. … 2. … [2] [Total: 9]

9 marks

Mark scheme: 5(a)(i) (most) calcium magnesium zinc (least) tin Ca most reactive & Sn least reactive ; Mg & Zn in the middle in the correct order ; 2 5(a)(ii) any two from increase temperature ; increase concentration (of acid) ; reduce particle size / use a powder / increase the surface area (of the metal) ; 2 5(b)(i) hydrogen / H2 ; 1 5(b)(ii) three correct ;; two or one correct ; 2 5(c) any two from: malleable ; (good) heat conductor ; (good) electrical conductor ; 2

This question in 0653/31 May/June 2019

8 (a) Aluminium reacts with iron oxide to form iron in an exothermic reaction. Aluminium does not react with calcium oxide. (i) Place the three metals, aluminium, iron and calcium, in order from most to least reactive. … most reactive … … least reactive [1] (ii) Complete the word equation for the reaction between aluminium and iron oxide. + aluminium oxide + [2] (iii) State whether aluminium is oxidised or reduced during this reaction. Explain your answer. aluminium is … explanation … … [1] (b) Copper oxide, CuO, contains copper(II) ions. When copper oxide is mixed with carbon, there is no reaction. (i) State what must be done to this mixture to obtain copper. … [1] (ii) State the test for copper(II) ions. Give the result that shows the presence of copper(II) ions. test … result … … [2] [Total: 7]

7 marks

Mark scheme: 8(a)(i) (most reactive) calcium / Ca aluminium / Al (least reactive) iron / Fe 1 8(a)(ii) LHS ; RHS ; aluminium + iron oxide Î (aluminium oxide) + iron 2 8(a)(iii) (aluminium is) oxidised and (explanation) it gains oxygen / reacts with oxygen 1 8(b)(i) heat / increase temperature ; 1 Question Answer Marks 8(b)(ii) (test) (aqueous) sodium hydroxide / (aqueous) ammonia ; (result from correct reagent) blue ppt ; 2

This question in 0653/32 May/June 2019

2 (a) A student investigates three solid elements, X, Y and Z. Element X is a dark grey solid. When it is warmed it turns to a purple vapour. Element Y is a soft grey solid. It reacts vigorously with water. Element Z is a dense grey solid. It has a high melting point. (i) Use the letters X, Y and Z to identify: a Group I element … a Group VII element … a transition element. … [2] (ii) Describe the trend in the melting points of the elements going down Group I. … … [1] (b) The student then investigates four other solid metals P, Q, R and S. He adds equal sized pieces of each metal to cold water and to dilute hydrochloric acid. Some of his observations are shown in Fig. 2.1. dilute dilute cold hydrochloric hydrochloric water acid acid P gas P gas Q gas bubbles bubbles bubbles cold dilute water hydrochloric acid gas R S bubbles Fig. 2.1 (i) Use the letters P, Q, R and S to identify these four metals. calcium … magnesium … iron … copper … [2] (ii) Suggest two ways of increasing the rate of reaction of metal Q with hydrochloric acid. 1 … 2 … [2] (iii) Identify the gas that is formed when metal S reacts with dilute hydrochloric acid. … [1] (iv) When metal S reacts with dilute hydrochloric acid, the temperature of the mixture increases. State the name given to a chemical reaction that causes the temperature to increase. … [1] [Total: 9]

9 marks

Mark scheme: 2(a)(i) Group I Y Group VII X transition element Z ;; one or two correct = 1 mark 2 2(a)(ii) decrease ; 1 Question Answer Marks 2(b)(i) calcium S magnesium P iron Q copper R ;; magnesium correct = 1 mark 2 2(b)(ii) any two from: increase concentration ; increase temperature ; (use a) catalyst ; Increase surface area of metal / (use) powder / smaller pieces (of metal) ; max 2 2(b)(iii) hydrogen / H2 ; 1 2(b)(iv) exothermic ; 1

This question in 0653/32 Feb/March 2020

8 (a) A student reacts a piece of magnesium with dilute hydrochloric acid, as shown in Fig. 8.1. A funnel holds the magnesium under a measuring cylinder to collect the gas formed. gas measuring cylinder dilute hydrochloric acid magnesium funnel Fig. 8.1 (i) State one other piece of apparatus that the student needs to use to determine the rate of this reaction. … [1] (ii) Suggest one change that increases the rate of this reaction. … [1] (iii) The student repeats the experiment under the same conditions, using the same mass of zinc instead of magnesium. State and explain the effect of this change on the rate of reaction. effect … explanation … [1] (b) Brass is a mixture of zinc and copper. (i) State the general name of mixtures such as brass that contain different metals. … [1] (ii) Suggest why brass, and not pure copper, is used to make coins. … … [1] (c) Some copper compounds are used as catalysts. Name the collection of metals in the Periodic Table that includes copper. … [1] (d) Copper is extracted from copper oxide using carbon. (i) Describe one condition needed for this process. … [1] (ii) State and explain whether copper is oxidised or reduced in this process. copper is … explanation … … [1] [Total: 8]

8 marks

Mark scheme: 8(a)(i) stop-clock ; 1 Question Answer Marks 8(a)(ii) any one from: increase temperature ; increase concentration (of acid) ; increase surface area (of Mg) / use Mg powder / use smaller pieces ; add a catalyst ; 1 8(a)(iii) effect: decrease / slower (rate) AND explanation: zinc is less reactive (than magnesium) ORA ; 1 8(b)(i) alloy ; 1 8(b)(ii) brass is, stronger / harder / less malleable / hardwearing / durable / corrodes or oxidises less / doesn’t go green ; 1 8(c) transition (elements / metals) ; 1 8(d)(i) high temperature ; 1 8(d)(ii) copper is: reduced AND explanation: (copper) loses, oxygen / O ; 1

This question in 0653/31 May/June 2021

5 (a) A student investigates the reaction between dilute hydrochloric acid and a 5.0 g piece of zinc using the apparatus shown in Fig. 5.1. gas apparatus X dilute hydrochloric acid stopwatch funnel to collect gas zinc Fig. 5.1 The reaction forms a gas and a solution containing a zinc salt. (i) Complete the word equation for this reaction. zinc + hydrochloric acid + [2] (ii) Name apparatus X. … [1] (iii) Describe a chemical test to show that the solution contains zinc ions, Zn2+. test … result … … [2] (iv) The student repeats the experiment under the same conditions, using 5.0 g of magnesium instead of zinc. State the change to the rate of the reaction, if any, that occurs when magnesium is used instead of zinc. Explain your answer. rate change … explanation … … [1] (b) Zinc and other metals are obtained from their ores. They are also obtained by recycling. Recycling metals costs less than obtaining metals from their ores. State one other reason why metals are recycled. … [1] (c) Lithium, sodium and potassium are Group I metals. Describe one chemical trend and one physical trend in the properties of these metals going down Group I from lithium to potassium. chemical trend … … physical trend … … [2] [Total: 9]

9 marks

Mark scheme: 5(a)(i) zinc + hydrochloric acid → zinc chloride + hydrogen zinc chloride ; hydrogen ; 2 5(a)(ii) measuring cylinder ; 1 5(a)(iii) test: aqueous NaOH OR aqueous ammonia ; result: white ppt. (soluble in excess) ; 2 5(a)(iv) rate change: increase / faster AND explanation: magnesium is more reactive (than zinc) ORA ; 1 5(b) ores are a finite resource / will run out ; 1 5(c) chemical trend: more reactive ; physical trend: lower melting point OR higher density ; 2

This question in 0653/32 May/June 2021

2 (a) The order of reactivity for some metals is shown in Fig. 2.1. most reactive metal A sodium calcium metal B zinc iron least reactive copper Fig. 2.1 (i) Suggest the identities of metals A and B. A … B … [1] (ii) State two observations for the reaction of sodium with water. 1 … 2 … [2] (b) Sodium is in Group I of the Periodic Table. Iron is a transition element. Describe two physical properties of iron that show that it is different from sodium. 1 … 2 … [2] (c) Brass is an alloy of zinc and one other metal. State the name of this other metal. … [1] (d) Recycling metals uses less energy and costs less money than extracting the metals from their ores. State one other reason why metals need to be recycled. … … [1] (e) Sodium and chlorine react together in an exothermic reaction to form sodium chloride. (i) State what is meant by exothermic. … … [1] (ii) Fig. 2.2 shows the electronic structures of a sodium ion, Na+, and a chloride ion, Cl–, in sodium chloride. sodium ion chloride ion ×× ×× ×× × × ×× ×× ×××× ×× ×× × × ×× ×× × × Fig. 2.2 Complete Fig. 2.3 to show the electronic structures of a sodium atom, Na, and a chlorine atom, Cl. sodium atom chlorine atom Fig. 2.3 [2] [Total: 10]

10 marks

Mark scheme: 2(a)(i) A potassium AND B magnesium / aluminium ; 1 2(a)(ii) any two from: fizzes / bubbles ; gets smaller ; floats ; moves ; 2 2(b) any two from: (iron has) high(er) density / ORA ; (iron has) high(er) melting point / ORA ; (iron is) magnetic / ORA ; 2 2(c) copper ; 1 2(d) metals are finite (resources) / will run out ; 1 2(e)(i) (thermal) energy is released ; 1 2(e)(ii) (sodium atom) 2, 8, 1 ; (chlorine atom) 2, 8, 7 ; 2

This question in 0653/31 Oct/Nov 2021

8 (a) Lithium, sodium and potassium are metals in Group I of the Periodic Table. Chlorine, bromine and iodine are halogens in Group VII of the Periodic Table. Helium, neon and argon are elements in Group VIII of the Periodic Table. (i) State the trend in the density of the elements going down Group I. … [1] (ii) State the trend in the colour of the elements going down Group VII. … [1] (iii) Identify one similarity between the elements in Group VIII. … [1] (b) Aluminium, calcium, iron and sodium are in different groups of the Periodic Table. Place these metals in order of reactivity, from most to least reactive. … most reactive … … … least reactive [2] (c) An atom of sodium is represented as shown. 23 11Na Deduce the number of protons and the number of neutrons in this atom. protons … neutrons … [2] (d) State one use of helium. … [1] [Total: 8]

8 marks

Mark scheme: 8(a)(i) increases (down the group) ; 1 8(a)(ii) (they get) darker ; 1 8(a)(iii) unreactive / inert ; 1 Question Answer Marks 8(b) sodium calcium aluminium iron ;; all correct (2) sodium is most reactive (1) 2 8(c) (protons) 11 ; (neutrons) 12 ; 2 8(d) filling balloons ; 1

This question in 0653/31 May/June 2022

2 (a) Zinc is extracted from zinc oxide by heating with carbon. The equation for this reaction is shown. zinc oxide + carbon zinc + carbon dioxide (i) State the type of chemical change that occurs when compounds lose oxygen. … [1] (ii) State the name given to any chemical reaction that absorbs (takes in) heat energy. … [1] (iii) Explain why zinc can be extracted from zinc oxide by heating with carbon but magnesium cannot be extracted from magnesium oxide by heating with carbon. … … … [2] (b) Excess zinc oxide is added to dilute sulfuric acid. A zinc salt and one other compound are formed. (i) Complete the word equation for this reaction. dilute sulfuric zinc oxide + + acid [2] (ii) Describe what happens to the pH value of the reaction mixture during this reaction. … … [1] (c) An atom of zinc is represented as shown. 6530Zn Deduce the number of electrons and the number of neutrons in this atom of zinc. electrons … neutrons … [2] [Total: 9]

9 marks

Mark scheme: 2(a)(i) reduction ; 1 2(a)(ii) endothermic ; 1 2(a)(iii) zinc / Zn is less reactive than carbon / C ; ORA magnesium / Mg is more reactive than carbon / C ; ORA 2 2(b)(i) zinc oxide + dilute sulfuric acid zinc sulfate ; + water ; 2 2(b)(ii) (pH) increases ; 1 Question Answer Marks 2(c) (electrons) 30 ; (neutrons) 35 ; 2

This question in 0653/32 May/June 2022

5 (a) Copper and aluminium are metals. They are extracted from their oxides by different methods. Copper is extracted from copper oxide by reaction with carbon. The equation for this reaction is shown. 2CuO + C 2Cu + CO2 During the reaction, the mass of the reaction mixture decreases, and the copper ions are reduced. (i) State one condition required for copper oxide to react with carbon. … [1] (ii) Explain why the mass of the reaction mixture decreases. … … [1] (iii) Use the equation for the reaction between copper oxide and carbon to explain what is meant by reduction. … … [1] (iv) Aluminium ore contains aluminium oxide. State the process used to extract aluminium from aluminium oxide. … [1] (b) Copper is a transition metal. Aluminium is a Group III metal. (i) Suggest one property of copper that is also a property of aluminium. … [1] (ii) Suggest two properties of copper that are not properties of aluminium. 1 … 2 … [2] (c) A student investigates the reactivities of copper, magnesium and two unknown metals, X and Y, as shown in Fig. 5.1. Metal X and magnesium are added to cold water. Copper and metal Y are added to dilute hydrochloric acid. metal X magnesium copper metal Y cold water dilute hydrochloric acid Fig. 5.1 Deduce the order of reactivity for these four metals. most reactive … … … least reactive … [2] [Total: 9]

9 marks

Mark scheme: 5(a)(i) high temperature ; 1 5(a)(ii) a gas is produced (that leaves the reaction mixture) ; 1 5(a)(iii) oxygen is, lost / removed (from the copper ions) ; 1 5(a)(iv) electrolysis ; 1 5(b)(i) any one from: 1 (good) conductor of electricity ; (good) conductor of heat ; high melting point ; high boiling point ; malleable ; 5(b)(ii) any two from: 2 copper / ORA, forms coloured compounds ; acts as catalyst ; has high density ; has high melting point ; 5(c) metal X 2 magnesium metal Y copper metal X (most reactive) and copper (least reactive) ; magnesium more reactive than metal Y;

This question in 0653/31 Oct/Nov 2022

5 (a) A student investigates the reaction of magnesium with dilute hydrochloric acid, as shown in Fig. 5.1. gas syringe bubble of gas dilute piece of hydrochloric magnesium acid Fig. 5.1 Magnesium chloride and a gas are produced. (i) Complete the word equation for this reaction. magnesium + + [2] (ii) Suggest one change that can be made to increase the rate of this reaction. … … [1] (iii) Suggest one metal that reacts with dilute hydrochloric acid with a lower rate of reaction than magnesium. … [1] (iv) Magnesium reacts with a different dilute acid to make magnesium sulfate. State the name of this acid. … [1] (v) Describe a chemical test for chloride ions and state the positive result. test … … result … [2] (b) The combustion of magnesium in air forms magnesium oxide, MgO. Magnesium oxide reacts slowly with carbon dioxide in the air to form magnesium carbonate, MgCO3, as shown in Fig. 5.2. combustion reaction in air magnesium with CO2 magnesium magnesium oxide carbonate Fig. 5.2 (i) Explain why the combustion of magnesium is described as oxidation. … … [1] (ii) The combustion of other substances produces carbon dioxide. State the name of one substance that produces carbon dioxide during combustion. … [1] (iii) Carbon dioxide is a greenhouse gas. State the name of one other greenhouse gas. … [1] [Total: 10]

10 marks

Mark scheme: 5(a)(i) 2 hydrogen ; hydrochloric acid AND magnesium chloride ; 5(a)(ii) any one from: 1 increase temperature / heat ; increase (acid) concentration ; use a catalyst ; use, powdered / smaller pieces of, magnesium ; 5(a)(iii) any one from: 1 aluminium / Al ; zinc / Zn ; iron / Fe ; 5(a)(iv) sulfuric (acid) ; 1 5(a)(v) test (acidified aqueous) silver nitrate ; 2 result white precipitate ; 5(b)(i) oxygen is, added / gained ; 1 5(b)(ii) any named carbon-containing compound ; 1 5(b)(iii) methane ; 1

This question in 0653/32 Oct/Nov 2022

5 (a) A student investigates the reaction of magnesium with dilute hydrochloric acid, as shown in Fig. 5.1. gas syringe bubble of gas dilute piece of hydrochloric magnesium acid Fig. 5.1 Magnesium chloride and a gas are produced. (i) Complete the word equation for this reaction. magnesium + + [2] (ii) Suggest one change that can be made to increase the rate of this reaction. … … [1] (iii) Suggest one metal that reacts with dilute hydrochloric acid with a lower rate of reaction than magnesium. … [1] (iv) Magnesium reacts with a different dilute acid to make magnesium sulfate. State the name of this acid. … [1] (v) Describe a chemical test for chloride ions and state the positive result. test … … result … [2] (b) The combustion of magnesium in air forms magnesium oxide, MgO. Magnesium oxide reacts slowly with carbon dioxide in the air to form magnesium carbonate, MgCO3, as shown in Fig. 5.2. combustion reaction in air magnesium with CO2 magnesium magnesium oxide carbonate Fig. 5.2 (i) Explain why the combustion of magnesium is described as oxidation. … … [1] (ii) The combustion of other substances produces carbon dioxide. State the name of one substance that produces carbon dioxide during combustion. … [1] (iii) Carbon dioxide is a greenhouse gas. State the name of one other greenhouse gas. … [1] [Total: 10]

10 marks

Mark scheme: 5(a)(i) 2 hydrogen ; hydrochloric acid AND magnesium chloride ; 5(a)(ii) any one from: 1 increase temperature / heat ; increase (acid) concentration ; use a catalyst ; use, powdered / smaller pieces of, magnesium ; 5(a)(iii) any one from: 1 aluminium / Al ; zinc / Zn ; iron / Fe ; 5(a)(iv) sulfuric (acid) ; 1 5(a)(v) test (acidified aqueous) silver nitrate ; 2 result white precipitate ; 5(b)(i) oxygen is, added / gained ; 1 5(b)(ii) any named carbon-containing compound ; 1 5(b)(iii) methane ; 1

This question in 0653/33 Oct/Nov 2022

2 A student investigates the reactions of four metals with dilute hydrochloric acid, HCl. (a) In the first experiment, the student adds a piece of each metal to separate test-tubes of dilute hydrochloric acid. The concentration and temperature of the acid are the same in each test-tube. The size of each piece of metal is the same, and the pieces of metal are added to the acid at the same time. The student observes bubbles of gas being produced in three of the test-tubes, as shown in Fig. 2.1. dilute hydrochloric acid bubble of gas copper zinc metal X metal Y Fig. 2.1 (i) State the name of the gas produced in this investigation. … [1] (ii) State the name of the salt made in the reaction between zinc and dilute hydrochloric acid. … [1] (iii) Explain why bubbles of gas are produced in the test-tube containing zinc, but no bubbles of gas are produced in the test-tube containing copper. … … [1] (iv) Suggest the identities of metal X and metal Y. Choose from the list of metals. aluminium calcium iron magnesium metal X … metal Y … [1] (b) In the second experiment, the student uses the apparatus shown in Fig. 2.2 to investigate the rate of reaction of zinc with dilute hydrochloric acid. gas W water dilute hydrochloric acid zinc Fig. 2.2 (i) State the name of the piece of apparatus labelled W. … [1] (ii) State one other piece of apparatus, not shown in Fig. 2.2, that the student uses to investigate the rate of this reaction. … [1] (iii) Suggest one way the student can increase the rate of this reaction. … … [1] (iv) When zinc reacts with dilute hydrochloric acid, an aqueous zinc salt is formed. This salt contains zinc ions, Zn2+. State a chemical test for zinc ions, Zn2+, and give the observation for a positive result. test … … observation … … [2] [Total: 9]

9 marks

Mark scheme: 2(a)(i) hydrogen ; 1 2(a)(ii) zinc chloride ; 1 2(a)(iii) zinc is more reactive (than copper / hydrogen) ORA ; 1 2(a)(iv) metal X: calcium / aluminium / magnesium ; 1 metal Y: iron ; 2(b)(i) measuring cylinder ; 1 2(b)(ii) stop-watch / timer ; 1 2(b)(iii) any one from: 1 increase concentration (of acid) ; increase temperature ; increase surface area of zinc / use smaller zinc pieces ; use a catalyst ; 2(b)(iv) test: aqueous sodium hydroxide / aqueous ammonia ; 2 result: white precipitate / solid AND solid is soluble in excess solution ;

This question in 0653/32 Oct/Nov 2023

2 A student investigates the reactions of four metals with dilute hydrochloric acid, HCl. (a) In the first experiment, the student adds a piece of each metal to separate test-tubes of dilute hydrochloric acid. The concentration and temperature of the acid are the same in each test-tube. The size of each piece of metal is the same, and the pieces of metal are added to the acid at the same time. The student observes bubbles of gas being produced in three of the test-tubes, as shown in Fig. 2.1. dilute hydrochloric acid bubble of gas copper zinc metal X metal Y Fig. 2.1 (i) State the name of the gas produced in this investigation. … [1] (ii) State the name of the salt made in the reaction between zinc and dilute hydrochloric acid. … [1] (iii) Explain why bubbles of gas are produced in the test-tube containing zinc, but no bubbles of gas are produced in the test-tube containing copper. … … [1] (iv) Suggest the identities of metal X and metal Y. Choose from the list of metals. aluminium calcium iron magnesium metal X … metal Y … [1] (b) In the second experiment, the student uses the apparatus shown in Fig. 2.2 to investigate the rate of reaction of zinc with dilute hydrochloric acid. gas W water dilute hydrochloric acid zinc Fig. 2.2 (i) State the name of the piece of apparatus labelled W. … [1] (ii) State one other piece of apparatus, not shown in Fig. 2.2, that the student uses to investigate the rate of this reaction. … [1] (iii) Suggest one way the student can increase the rate of this reaction. … … [1] (iv) When zinc reacts with dilute hydrochloric acid, an aqueous zinc salt is formed. This salt contains zinc ions, Zn2+. State a chemical test for zinc ions, Zn2+, and give the observation for a positive result. test … … observation … … [2] [Total: 9]

9 marks

Mark scheme: 2(a)(i) hydrogen ; 1 2(a)(ii) zinc chloride ; 1 2(a)(iii) zinc is more reactive (than copper / hydrogen) ORA ; 1 2(a)(iv) metal X: calcium / aluminium / magnesium ; 1 metal Y: iron ; 2(b)(i) measuring cylinder ; 1 2(b)(ii) stop-watch / timer ; 1 2(b)(iii) any one from: 1 increase concentration (of acid) ; increase temperature ; increase surface area of zinc / use smaller zinc pieces ; use a catalyst ; 2(b)(iv) test: aqueous sodium hydroxide / aqueous ammonia ; 2 result: white precipitate / solid AND solid is soluble in excess solution ;

This question in 0653/33 Oct/Nov 2023

2 A student investigates the rate of reaction between pieces of calcium metal and dilute hydrochloric acid. The mass is recorded every 30 s during the reaction. Fig. 2.1 shows the apparatus. cotton wool conical flask bubbles of hydrogen gas dilute hydrochloric acid pieces of calcium metal balance 210 . 25 g Fig. 2.1 (a) The reaction produces hydrogen gas. (i) Complete the word equation for this reaction. + + hydrogen [2] (ii) Describe the test for hydrogen gas. State the observation for the positive result. test … observation … [2] (iii) The conical flask becomes hot during the reaction. State the term for chemical reactions that release heat. … [1] (b) The student repeats the experiment using iron, magnesium and zinc instead of calcium. The pieces of metal used are all the same size. The dilute hydrochloric acid is in excess. Table 2.1 shows the results. Table 2.1 mass of conical flask + acid + metal time / g / s calcium iron magnesium zinc 0 210.25 211.55 212.50 209.50 30 209.35 211.25 211.80 209.10 60 208.30 210.85 210.90 208.70 90 207.20 210.50 210.15 208.35 120 206.30 210.15 209.40 207.80 (i) Table 2.2 shows the change in mass for three of the metals. Complete Table 2.2 by calculating the change in mass for zinc. Table 2.2 metal change in mass / g calcium 3.95 iron 1.40 magnesium 3.10 zinc [1] (ii) Use the information in Table 2.1 and Table 2.2 to identify the least reactive metal. Explain your answer. metal … explanation … … [2] (c) Iron is a transition element. (i) State two physical properties of iron. 1 … 2 … [2] (ii) Iron is used to make alloys. Suggest why alloys are used instead of pure metals. … … [1] [Total: 11]

11 marks

Mark scheme: 2(a)(i) calcium AND hydrochloric acid ; 2 calcium chloride ; 2(a)(ii) lighted splint ; 2 pop(s) ; 2(a)(iii) exothermic ; 1 2(b)(i) 1.70 (g) ; 1 2(b)(ii) iron ; 2 smallest change in mass ; 2(c)(i) any two from: 2 high melting point ; malleable ; good conductor of heat ; good conductor of electricity ; 2(c)(ii) general statement that alloys have, better / different / desired, properties OR 1 named property, e.g. harder, greater resistance to corrosion, stronger ;

This question in 0653/32 Oct/Nov 2024

2 A student investigates the rate of reaction between pieces of calcium metal and dilute hydrochloric acid. The mass is recorded every 30 s during the reaction. Fig. 2.1 shows the apparatus. cotton wool conical flask bubbles of hydrogen gas dilute hydrochloric acid pieces of calcium metal balance 210 . 25 g Fig. 2.1 (a) The reaction produces hydrogen gas. (i) Complete the word equation for this reaction. + + hydrogen [2] (ii) Describe the test for hydrogen gas. State the observation for the positive result. test … observation … [2] (iii) The conical flask becomes hot during the reaction. State the term for chemical reactions that release heat. … [1] (b) The student repeats the experiment using iron, magnesium and zinc instead of calcium. The pieces of metal used are all the same size. The dilute hydrochloric acid is in excess. Table 2.1 shows the results. Table 2.1 mass of conical flask + acid + metal time / g / s calcium iron magnesium zinc 0 210.25 211.55 212.50 209.50 30 209.35 211.25 211.80 209.10 60 208.30 210.85 210.90 208.70 90 207.20 210.50 210.15 208.35 120 206.30 210.15 209.40 207.80 (i) Table 2.2 shows the change in mass for three of the metals. Complete Table 2.2 by calculating the change in mass for zinc. Table 2.2 metal change in mass / g calcium 3.95 iron 1.40 magnesium 3.10 zinc [1] (ii) Use the information in Table 2.1 and Table 2.2 to identify the least reactive metal. Explain your answer. metal … explanation … … [2] (c) Iron is a transition element. (i) State two physical properties of iron. 1 … 2 … [2] (ii) Iron is used to make alloys. Suggest why alloys are used instead of pure metals. … … [1] [Total: 11]

11 marks

Mark scheme: 2(a)(i) calcium AND hydrochloric acid ; 2 calcium chloride ; 2(a)(ii) lighted splint ; 2 pop(s) ; 2(a)(iii) exothermic ; 1 2(b)(i) 1.70 (g) ; 1 2(b)(ii) iron ; 2 smallest change in mass ; 2(c)(i) any two from: 2 high melting point ; malleable ; good conductor of heat ; good conductor of electricity ; 2(c)(ii) general statement that alloys have, better / different / desired, properties OR 1 named property, e.g. harder, greater resistance to corrosion, stronger ;

This question in 0653/33 Oct/Nov 2024

4 A student investigates the reaction between magnesium and steam. Fig. 4.1 is a diagram of the apparatus used in the investigation. cotton wool magnesium soaked gas jar ribbon in water gas heat heat Fig. 4.1 (a) The reaction produces magnesium oxide and a gas. (i) Complete the word equation for this reaction. magnesium + + oxide [2] (ii) The gas jar in Fig. 4.1 collects the gas, but it does not allow the volume to be measured directly. Name one piece of apparatus that allows the volume of gas to be measured directly. … [1] (iii) Complete the sentences about the reaction of magnesium with steam. Use words from the list. Each word may be used once, more than once or not at all. anions cations covalent electrons ionic neutrons neutralisation oxidation protons reduction During the reaction, magnesium atoms lose … to form positive ions. These positive ions are known as … . Oxygen atoms from the water molecules form negative ions. Positive ions and negative ions attract each other and form … bonds. During the reaction, magnesium atoms gain oxygen. This type of reaction is … . [4] (b) The student repeats the experiment using copper instead of magnesium. Predict what the student observes during the reaction. Explain your answer. observation … … explanation … … [2] [Total: 9]

9 marks

Mark scheme: 4(a)(i) magnesium AND water ; 2 hydrogen ; 4(a)(ii) measuring cylinder / gas syringe ; 1 4(a)(iii) electrons ; 4 cations ; ionic ; oxidation ; 4(b) observation: 2 no effervescence / no bubbles ; explanation: idea that copper is less reactive / unreactive ;

This question in 0653/32 Oct/Nov 2025

4 A student investigates the reaction between magnesium and steam. Fig. 4.1 is a diagram of the apparatus used in the investigation. cotton wool magnesium soaked gas jar ribbon in water gas heat heat Fig. 4.1 (a) The reaction produces magnesium oxide and a gas. (i) Complete the word equation for this reaction. magnesium + + oxide [2] (ii) The gas jar in Fig. 4.1 collects the gas, but it does not allow the volume to be measured directly. Name one piece of apparatus that allows the volume of gas to be measured directly. … [1] (iii) Complete the sentences about the reaction of magnesium with steam. Use words from the list. Each word may be used once, more than once or not at all. anions cations covalent electrons ionic neutrons neutralisation oxidation protons reduction During the reaction, magnesium atoms lose … to form positive ions. These positive ions are known as … . Oxygen atoms from the water molecules form negative ions. Positive ions and negative ions attract each other and form … bonds. During the reaction, magnesium atoms gain oxygen. This type of reaction is … . [4] (b) The student repeats the experiment using copper instead of magnesium. Predict what the student observes during the reaction. Explain your answer. observation … … explanation … … [2] [Total: 9]

9 marks

Mark scheme: 4(a)(i) magnesium AND water ; 2 hydrogen ; 4(a)(ii) measuring cylinder / gas syringe ; 1 4(a)(iii) electrons ; 4 cations ; ionic ; oxidation ; 4(b) observation: 2 no effervescence / no bubbles ; explanation: idea that copper is less reactive / unreactive ;

This question in 0653/33 Oct/Nov 2025