Transition elements — Paper 3 · IGCSE Science - Combined 0653

8 (a) A student observes what happens when a piece of sodium is added to water, as shown in Fig. 8.1. sodium water Fig. 8.1 During the reaction the student observes that the sodium floats and melts. The student is told that sodium hydroxide solution is formed and hydrogen gas is given off. (i) State which information above shows that sodium has a low density. … [1] (ii) Complete the word equation for this reaction. + + [2] (iii) The student makes different observations when a piece of copper is added to water. Describe these different observations. 1. … 2. … [2] (b) The Periodic Table contains groups and collections of elements. (i) Name the collection of metals which often act as catalysts. … [1] (ii) Describe the reactivity of the noble gases. … [1] (iii) Chlorine, Cl, is in Group VII of the Periodic Table. An atom of chlorine is represented as: 3517Cl The mass number is 35, and the atomic number is 17. Explain what is meant by mass number, … … atomic number. … … [2]

9 marks

Mark scheme: 8(a)(i) floats ; 1 8(a)(ii) LHS (either order) ; RHS (either order) ; sodium + water Î sodium hydroxide + hydrogen 2 8(a)(iii) sinks ; no reaction ; either order 2 8(b)(i) transition metals ; 1 8(b)(ii) unreactive ; 1 8(b)(iii) mass no. (35) number of protons + neutrons ; atomic no. (17) number of protons ; 2

This question in 0653/32 Feb/March 2017

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) Some iron objects are shown in Fig. 2.1. Fig. 2.1 (i) State two physical properties of all metals. 1. … 2. … [2] (ii) Iron is a transition metal. State one physical property of transition metals that is not a physical property of Group I metals. … [1] (b) A student adds some iron nails to dilute sulfuric acid. Iron sulfate and hydrogen gas are produced. (i) Complete the word equation to show this reaction. iron + + [1] (ii) The student tests another dilute acid with aqueous silver nitrate. A white solid forms. Deduce the anion present and name the acid. anion … acid … [2] (c) The atomic number of iron is 26. Explain what is meant by atomic number. … … [1]

7 marks

Mark scheme: 2(a)(i) Any two from electrical conductor ; thermal / heat conductor ; malleable ; ductile ; sonorous ; max 2 2(a)(ii) high density / high melting point / coloured compounds ; 1 2(b)(i) (iron) + sulfuric acid Î iron sulfate + hydrogen ; 1 2(b)(ii) (anion) chloride ; (acid) hydrochloric (acid) ; 2 2(c) number of protons in an atom / nucleus ; 1

This question in 0653/33 Oct/Nov 2017

2 (a) Copper is extracted from a substance using the apparatus shown in Fig. 2.1. low voltage d.c. supply − + … … … Fig. 2.1 (i) Name this process. … [1] (ii) Complete Fig. 2.1 by labelling the anode, cathode and electrolyte. [2] (iii) Name one compound that can be used in this process to extract copper at room temperature. … [1] (iv) State what is done to this solid compound before it can be used in this process. … [1] (v) State whether this process for the extraction of copper involves a chemical change or a physical change. Explain your answer. change … explanation … … [1] (b) A student finds out that copper can also be extracted by heating a different compound, copper oxide, with a non-metallic element. (i) Name this non-metallic element. … [1] (ii) Name the type of chemical reaction in which copper oxide is changed to copper. … [1] (c) Copper is one element in a collection of metals which have high melting points, high densities and often act as catalysts. (i) Suggest one other property that is shown by these metals that is not shown by other metals. … [1] (ii) State the effect of a catalyst on a chemical reaction. … [1]

10 marks

Mark scheme: 2(a)(i) electrolysis ; 1 2(a)(ii) ;; all three correct (2) one or two correct (1) 2 cathode anode electrolyte Question Answer Marks 2(a)(iii) copper chloride / other soluble copper compound ; 1 2(a)(iv) dissolve in water ; 1 2(a)(v) chemical and new substance(s) made ; 1 2(b)(i) carbon / hydrogen ; 1 2(b)(ii) reduction ; 1 2(c)(i) form coloured compounds ; 1 2(c)(ii) increases reaction rate ; 1

This question in 0653/32 Feb/March 2018

2 (a) A student makes a salt using the apparatus shown in Fig. 2.1. process A process B powdered metal carbonate dilute sulfuric acid gentle heat Fig. 2.1 (i) Name process A and process B. process A … process B … [2] (ii) The student uses 1 g of the powdered metal carbonate. Describe the effect of using a single 1 g piece of the metal carbonate on the rate of this reaction. … [1] (iii) Describe the effect of using the same volume of a more concentrated sulfuric acid on the rate of this reaction. … [1] (iv) When the metal carbonate is mixed with dilute sulfuric acid, the temperature increases. State the name given to chemical reactions that cause the temperature to increase. … [1] (b) The student mixes copper carbonate with dilute sulfuric acid. Copper(II) sulfate and a colourless gas and a colourless liquid are formed. (i) Complete the word equation for this reaction. copper + + +carbonate [2] (ii) Describe a test for aqueous copper(II) ions. State the observations that show copper(II) ions are present. test … observations … … [2] (iii) Copper is a transition metal. It forms coloured compounds. Describe one other property of a transition metal. … [1]

10 marks

Mark scheme: 2(a)(i) (process A) filtration / filtering / filter ; (process B) evaporation ; 2 2(a)(ii) decreases ; 1 2(a)(iii) increases ; 1 2(a)(iv) exothermic ; 1 2(b)(i) (copper carbonate) + sulfuric acid Î copper sulfate + carbon dioxide + water sulfuric acid LHS AND copper sulfate RHS ; carbon dioxide AND water RHS ; 2 2(b)(ii) (test) (add) aqueous sodium hydroxide OR aqueous ammonia ; (observations) (light) blue precipitate OR blue ppt (then deep blue solution) ; 2 2(b)(iii) high density / high melting point / (element or compound) act as catalysts ; 1

This question in 0653/32 Oct/Nov 2018

8 (a) An atom of aluminium is represented by the symbol: 2 1 37Al State the number of protons and the number of neutrons in this atom. protons … neutrons … [2] (b) Aluminium is extracted from aluminium oxide. Aluminium oxide is obtained from the ore bauxite. (i) State the method of extraction used. … [1] (ii) State the type of bonding in aluminium oxide. … [1] (iii) Suggest one reason, other than cost, why aluminium is recycled. … … [1] (c) Copper forms coloured compounds, but aluminium does not. Explain this observation. … … [1] (d) Copper is extracted from copper oxide by heating with a non-metallic element. (i) Name this non-metallic element. … [1] (ii) State whether the copper oxide is oxidised or reduced during this process. Explain your answer. copper oxide is … explanation … … [1] [Total: 8]

8 marks

Mark scheme: 8(a) (protons) 13 ; (neutrons) 14 ; 2 8(b)(i) electrolysis ; 1 8(b)(ii) ionic ; 1 8(b)(iii) It is a finite resource / (they’re) running out / will run out / more energy used for extraction / less energy to recycle (than extract) / no need to mine / does not go into landfill ; 1 8(c) copper / Cu is a transition metal / aluminium is not a transition metal ; 1 8(d)(i) carbon ; 1 8(d)(ii) (copper oxide is) reduced and (explanation) (CuO) loses oxygen ; 1

This question in 0653/31 May/June 2019

2 (a) Element A is in Group III in the Periodic Table. Element B is in Group VII in the Periodic Table. Elements A and B are in the same period in the Periodic Table. (i) Suggest which element, A or B, has more metallic character. Explain your answer. element … explanation … … [1] (ii) Element C is below element B in Group VII. Suggest which element, B or C, has: a darker colour … a lower boiling point. … [1] (b) Element D is a monoatomic gas that is used to provide an inert atmosphere. Element E has a high density and is often used as a catalyst. State the group number or the name of the collection of elements for elements D and E in the Periodic Table. element D … element E … [2] (c) A student adds excess copper oxide powder to dilute sulfuric acid to make copper sulfate and one other product. (i) Complete the word equation for the reaction between copper oxide and dilute sulfuric acid. + + [2] (ii) Explain why copper oxide is added in excess. … … [1] (iii) The type of chemical bond that forms between copper and oxygen is the same as the type of chemical bond that forms between sodium and chlorine. State this type of chemical bond. Use ideas about electrons to explain how these bonds form. bond … explanation … … [2] [Total: 9]

9 marks

Mark scheme: 2(a)(i) A and it is on left of the Periodic Table ; 1 2(a)(ii) C and B ; 1 2(b) (element D) noble gases / Group VIII / Group 0 ; (element E) transition metals / transition elements ; 2 2(c)(i) reactants ; products ; 2 2(c)(ii) to make sure all the acid is used up ; 1 Question Answer Marks 2(c)(iii) (bond) ionic ; (explanation) (electron) transfer / loss and gain ; 2

This question in 0653/31 Oct/Nov 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 Period 4 of the Periodic Table is shown in Fig. 8.1. It contains the elements from potassium, K, to krypton, Kr. Group I II III IV V VI VII VIII 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 39 40 45 48 51 52 55 56 59 59 64 65 70 73 75 79 80 84 Key atomic number atomic symbol relative atomic mass Fig. 8.1 (a) State the trend in the metallic character of the elements from potassium to krypton. … to … [1] (b) Iron is in a collection of elements between calcium, Ca, and gallium, Ga, in period 4. These elements have high densities and form coloured compounds. (i) State the name of this collection of elements. … [1] (ii) Describe one other property shown by these elements. … [1] (c) Chlorine is a gas in Group VII. It is made by passing electricity through an aqueous salt. (i) Name the process which uses electricity to break down an aqueous salt. … [1] (ii) Suggest one aqueous salt that is used to make chlorine in this process. … [1] (iii) Describe a chemical test for chlorine and the positive result for this test. test … result … [2] (iv) State the name of the collection of elements in Group VII. … [1] (d) Krypton is a gas in Group VIII (Group 0) in the Periodic Table. Complete the sentence about this group. The Group VIII (Group 0) gases are known as the … gases. [1] [Total: 9]

9 marks

Mark scheme: 8(a) metal(lic) (to) non-metal(lic) ; 1 8(b)(i) transition (elements / metals) ; 1 8(b)(ii) high melting points OR (act as) catalyst (as element or compound) ; 1 8(c)(i) electrolysis ; 1 8(c)(ii) (concentrated) sodium chloride ; 1 8(c)(iii) (test) damp (blue) litmus paper ; (result) (turns) red / bleaches ; 2 8(c)(iv) halogens ; 1 Question Answer Marks 8(d) noble ; 1

This question in 0653/31 May/June 2020

2 (a) A teacher puts a small piece of sodium onto water in a water trough, as shown in Fig. 2.1. sodium water water trough Fig. 2.1 The students observe the reaction between sodium and water. The teacher repeats the experiment using potassium instead of sodium. (i) Describe one similarity in the reactions of potassium and of sodium with water. … [1] (ii) Describe one difference between the observations for the reactions of potassium and of sodium with water. Explain the reason for this difference. difference … explanation … [2] (b) Iron is in a collection of metals in the Periodic Table shown on page 20. (i) Name this collection of metals. … [1] (ii) State one physical property of iron that is also a physical property of sodium. … [1] (iii) State one property of iron that is not a property of sodium. … [1] (c) The metals aluminium, copper and iron can be recycled. State one reason, other than cost, why these metals can be recycled. … … [1] (d) An atom of aluminium is represented by the symbol shown. 2 1 37Al (i) Complete Fig. 2.2 to show the electronic structure of this atom. Fig. 2.2 [2] (ii) Describe how this atom forms an aluminium ion, Al 3+. … … [1] [Total: 10]

10 marks

Mark scheme: 2(a)(i) any one from: exothermic / releases heat ; fizzes / releases gas / H2 ; forms an alkaline solution ; max 1 2(a)(ii) (difference) (potassium) burns / produces flames ; (explanation) (potassium is) more reactive (than sodium) ; 2 2(b)(i) transition (elements) ; 1 2(b)(ii) any one from: (good) conductor of electricity ; (good) conductor of heat ; malleable ; 1 Question Answer Marks 2(b)(iii) any one from: high melting point ; high boiling point ; high density ; forms coloured compounds ; (acts as) catalyst (as element or in compounds) ; 1 2(c) (they are) finite resources / (they’re) running out / will run out / more energy used for extraction / less energy to recycle (than extract) / no need to mine / does not go into landfill ; 1 2(d)(i) 2, 8, 3 shown correctly ;; (if incorrect allow 1 mark for 13 electrons drawn) 2 2(d)(ii) loss of electrons ; 1

This question in 0653/32 May/June 2020

5 (a) The water tap shown in Fig. 5.1 is made of brass. Fig. 5.1 Brass is made by mixing molten copper with molten zinc. The mixture is then allowed to cool to form solid brass. (i) State how solid copper is changed into molten copper. … … [1] (ii) Describe two differences between the arrangement of atoms in solid copper and the arrangement of atoms in molten copper. 1 … … 2 … … [2] (iii) State whether this process of making brass is a chemical change or a physical change. Explain your answer. change … explanation … … [1] (b) Copper is a transition element. Sodium is a Group I metal. (i) Describe two physical properties of copper that are not properties of sodium. 1 … 2 … [2] (ii) Describe one physical property of copper that is also a property of sodium. … [1] (c) Group I is on the left of the Periodic Table. Transition elements are found in the middle of the Periodic Table. Describe the change in the character of elements across a period, from left to right. … [1] [Total: 8]

8 marks

Mark scheme: 5(a)(i) heat / heating ; 1 5(a)(ii) (in solid copper, atoms are) in fixed position ; regular (arrangement) ; 2 5(a)(iii) (change) physical AND (explanation) no new substance is made / no chemical reaction ; 5(b)(i) high density ; high melting point ; 2 5(b)(ii) any one from: high boiling point ; malleable ; (good) conductor (of heat / electricity) ; 1 5(c) metallic to non-metallic ; 1

This question in 0653/33 Oct/Nov 2020

5 (a) An iron paperclip, shown in Fig. 5.1, is used to hold pieces of paper together. Fig. 5.1 Iron can be described as a strong metal. Name one other property of iron that makes it suitable for use as a paperclip. … [1] (b) A spanner, shown in Fig. 5.2, is made from an alloy of iron. Fig. 5.2 (i) Describe what is meant by an alloy. … … [1] (ii) Suggest why the spanner is made from an alloy of iron and not from pure iron. … … [1] (c) Lithium, sodium and potassium are Group I metals. Describe the trend in density and the trend in reaction with water of the Group I metals going down the group. density … … reaction with water … … [2] (d) Copper and iron are part of a collection of metals in the Periodic Table. (i) State the name of this collection of metals. … [1] (ii) Copper and iron are less reactive than Group I metals. Copper and iron have high melting points and high densities, but Group I metals do not. State one other property of copper and iron that is not a property of Group I metals. … [1] (e) When sodium reacts with chlorine, sodium chloride is formed. Fig. 5.3 shows the electronic structures of a sodium atom and of a chlorine atom. sodium atom chlorine atom Fig. 5.3 Sodium chloride contains sodium ions and chloride ions. Complete Fig. 5.4 to show the electronic structures of a sodium ion and a chloride ion. sodium ion chloride ion Fig. 5.4 [2] [Total: 9]

9 marks

Mark scheme: 5(a) malleable ; 1 5(b)(i) a mixture of a metal with other element(s) ; 1 5(b)(ii) pure iron is too soft / alloys are stronger / alloys resist, corrosion / rusting ; 1 5(c) (density) increases (down the group) ; (reaction with water) reactivity increases (down the group) ; 2 5(d)(i) transition (elements/metals) ; 1 5(d)(ii) form coloured compounds / (act as) catalysts ; 1 5(e) (sodium ion) 2,8 ; (chloride ion) 2,8,8 ; 2

This question in 0653/32 Feb/March 2021

5 (a) Copper is extracted from copper(II) oxide by heating with carbon. (i) Complete the word equation for this reaction. + copper + [2] (ii) Copper(II) oxide is reduced to copper in this reaction. Explain what is meant by the term reduced. … … [1] (b) Brass is a mixture of copper and zinc. (i) State the name of this type of mixture. … [1] (ii) Door keys are sometimes made from brass. Suggest why brass, rather than pure copper, is used to make door keys. … … [1] (c) Aluminium is extracted from aluminium oxide. (i) The ratio of aluminium atoms to oxygen atoms in aluminium oxide is shown. Al : O 1 : 1.5 Deduce the formula of aluminium oxide. … [1] (ii) State the method used to extract aluminium from aluminium oxide. … [1] (iii) Suggest why carbon cannot be used to extract aluminium from aluminium oxide. Use ideas about reactivity in your answer. … … [1] (d) Copper is a transition element. Aluminium is not a transition element. (i) Suggest one property of copper that is not shown by aluminium. … [1] (ii) Suggest one physical property that is shown by both copper and aluminium. … [1] [Total: 10]

10 marks

Mark scheme: 5(a)(i) copper oxide + carbon → copper + carbon dioxide LHS correct (either order) ; RHS correct ; 2 5(a)(ii) loss of oxygen (from copper oxide) ; 1 5(b)(i) alloy ; 1 5(b)(ii) brass is, hard-wearing / harder / stronger / corrosion resistant ; 1 5(c)(i) Al2O3 ; 1 5(c)(ii) electrolysis ; 1 5(c)(iii) carbon is less reactive (than aluminium) / aluminium is more reactive (than either carbon or copper) ; 1 5(d)(i) (copper) forms coloured compounds / catalytic activity / higher density / higher melting point ; 1 5(d)(ii) (electrical / heat / thermal) conductor / malleable / ductile ; 1

This question in 0653/33 May/June 2021

8 Part of the Periodic Table is shown in Fig. 8.1. Group I II III IV V VI VII VIII H He hydrogen helium Li Be B C N O F Ne lithium beryllium boron carbon nitrogen oxygen fluorine neon Na Mg Al Si P S Cl Ar sodium magnesium aluminium silicon phosphorus sulfur chlorine argon K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton Fig. 8.1 (a) Fluorine, chlorine and bromine are Group VII diatomic non-metals. (i) Describe the trend in the physical states of the elements going down Group VII. … … [1] (ii) Explain what is meant by diatomic. … … [1] (b) Chromium, cobalt and copper are part of a collection of elements which have high densities and high melting points. (i) State the name of this collection of elements. … [1] (ii) Describe one other property of these elements. … [1] (c) Argon is one of the Group VIII gases. (i) State one use for argon. … [1] (ii) Explain why the elements in Group VIII of the Periodic Table are unreactive. Use ideas about electronic structure in your answer. … … … [2] [Total: 7]

7 marks

Mark scheme: 8(a)(i) gas to liquid (to solid) ; 1 8(a)(ii) two atoms in (one / each) molecule ; 1 8(b)(i) transition (elements / metals) ; 1 8(b)(ii) any one from: form coloured compounds ; (element or compounds) act as catalysts ; AVP e.g. good conductors of electricity ; 1 8(c)(i) (provides inert atmosphere) in lamps / light bulbs ; AVP e.g. used in welding 1 8(c)(ii) they have a full outer shell of electrons ; so are stable / they do not need to gain, lose or share electrons to become stable ; 2

This question in 0653/32 Feb/March 2022

5 Copper is a transition element. (a) State two properties of transition elements that are not properties of Group I metals. 1 … 2 … [2] (b) Copper is extracted from copper oxide by heating with carbon. Identify the greenhouse gas formed in this process. … [1] (c) Copper is slowly oxidised by oxygen when it is left in air. The reaction equation is shown. 2Cu(s) + O2(g) 2CuO(s) (i) State the meaning of the term oxidised. … … [1] (ii) Suggest one change that increases the rate of this reaction. … [1] (d) (i) State the percentage of oxygen in clean air. … % [1] (ii) Suggest the percentage of argon in clean air. … % [1] (iii) State why argon does not react with copper. … … [1] [Total: 8]

8 marks

Mark scheme: 5(a) any two from: 2 high density ; high melting point ; (forms) coloured compounds ; (can) act as catalysts (as element or compound) ; 5(b) carbon dioxide / CO2 ; 1 5(c)(i) (it) gains oxygen ; 1 5(c)(ii) any one from: 1 increase / higher, temperature / heat (it) ; increase surface area ; 5(d)(i) 21(%) ; 1 5(d)(ii) less than 1(%) ; 1 5(d)(iii) argon is inert / argon is a noble gas / argon atoms have full outer shell ; 1

This question in 0653/32 Feb/March 2023

5 Copper is a transition element. (a) (i) State one physical property and one chemical property of copper. physical property … chemical property … [2] (ii) Suggest why some coins are made of copper alloy rather than pure copper. … … [1] (b) Copper is extracted from copper oxide by heating with carbon. Aluminium is extracted from aluminium oxide by electrolysis. Argon, a noble gas, does not react with copper or aluminium. (i) Complete the balanced equation for the extraction of copper. … CuO + … C … CO2 + … Cu [1] (ii) State whether carbon is oxidised or reduced during the extraction of copper. Give a reason for your answer. carbon is … reason … … [1] (iii) State why aluminium cannot be extracted from aluminium oxide by heating with carbon. … … [1] (iv) Explain why argon and other noble gases do not react with either copper or aluminium. Use ideas about noble gas electronic structures in your answer. … … … [2] [Total: 8]

8 marks

Mark scheme: 5(a)(i) (physical property) high density / high melting point / electrical conductor / heat or thermal conductor ; (chemical property) low reactivity ; 2 5(a)(ii) stronger / harder ; 1 5(b)(i) ..2..CuO + ..(1)..C  ..(1)..CO2 + ..2..Cu ; 1 5(b)(ii) (carbon is) oxidised AND (reason) it gains oxygen ; 1 5(b)(iii) aluminium is more reactive (than carbon) ; 1 Question Answer Marks 5(b)(iv) any two from: noble gases / argon, are, unreactive / inert ; (because) they have full outer electron shells ; do not lose / gain, electrons ; 2

This question in 0653/32 May/June 2023

8 The Periodic Table contains groups and collections of different elements. (a) Fig. 8.1 lists some of the elements in Group I. 3 Li lithium 7 11 Na sodium 23 19 K potassium 39 Fig. 8.1 The elements in Group I react with water to produce a gas. (i) State the name of this gas. … [1] (ii) State the trend in the reactivity of the elements down Group I. … [1] (b) Fig. 8.2 lists some of the elements in Group VII. 17 Cl chlorine 35.5 35 Br bromine 80 53 I iodine 127 Fig. 8.2 The elements in Group VII exist as diatomic molecules. (i) State what is meant by diatomic. … [1] (ii) State the trend in the colour of the elements down Group VII. … [1] (c) Iron and copper are part of a collection of metals which have high densities. (i) State the name of this collection of metals. … [1] (ii) Iron and copper and their compounds act as catalysts. State one other property of these metals that is not a property of Group I metals. … [1] (d) Argon and helium are noble gases. Argon is used in lamps, and helium is used in balloons, as shown in Fig. 8.3. argon helium Fig. 8.3 Identify one property of each element that makes it suitable for the use shown in Fig. 8.3. argon … helium … [2] [Total: 8]

8 marks

Mark scheme: 8(a)(i) hydrogen ; 1 8(a)(ii) increases (going down) ; 1 8(b)(i) contains two atoms (chemically) joined or bonded / a molecule containing two atoms ; 1 8(b)(ii) (become) darker / deeper ; 1 8(c)(i) transition (elements / metals) ; 1 8(c)(ii) high melting points / form coloured compounds ; 1 8(d) (argon) unreactive ; (helium) low density ; 2

This question in 0653/33 May/June 2023

5 Part of the Periodic Table is shown in Fig. 5.1. Group I II III IV V VI VII VIII H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Fig. 5.1 (a) (i) Draw one straight line to show the trend in metallic character across a period. decreases across a period from left to right metallic increases across a period character from left to right stays the same across a period from left to right [1] (ii) State the name of the collection of metals that includes iron, Fe, and copper, Cu. … [1] (b) Lithium, Li, sodium, Na, and potassium, K, are in Group I of the Periodic Table. State the trend in the melting point and the trend in the reaction with water of these elements going down Group I. melting point … … reaction with water … … [2] (c) Sodium, Na, reacts with fluorine, F, to form sodium fluoride. Fig. 5.2 shows the electronic structure of a sodium atom and of a fluorine atom. sodium atom fluorine atom Fig. 5.2 When sodium atoms react with fluorine atoms, sodium ions and fluoride ions form. Complete the dot-and-cross diagrams in Fig. 5.3 to show all of the electrons in a sodium ion and in a fluoride ion. sodium ion fluoride ion Fig. 5.3 [2] (d) The electronic structure of an atom of element Z is shown in Fig. 5.4. element Z Fig. 5.4 (i) Use the Periodic Table to identify element Z. … [1] (ii) Sodium and element Z do not easily form a compound together. Use the electronic structure shown in Fig. 5.4 to explain this observation. … … … [2] [Total: 9]

9 marks

Mark scheme: 5(a)(i) metallic character - decreases across a period from left to right ; 1 5(a)(ii) transition (elements) ; 1 5(b) (melting point) decreases (down Group I) ; (reaction with water) more reactive / reacts more vigorously / reacts faster (down Group I) ; 2 5(c) (sodium ion) 2 electrons in 1st shell, 8 in 2nd shell only (no electrons in 3rd shell) ; (fluoride ion) 2 electrons in 1st shell, 8 in 2nd shell only ; 2 5(d)(i) argon ; 1 5(d)(ii) Z has full outer shell / 8 electrons in outer shell ; Z does not need to gain an electron (from sodium) / Z has a stable electron arrangement ; 2

This question in 0653/33 May/June 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 0653/32 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

5 (a) Iron is a transition element. Tick () two boxes that show correct statements about the properties of iron and Group I elements. Iron and Group I elements conduct electricity. Iron has a higher melting point than Group I elements. Group I elements have a higher density than iron. Group I elements form coloured compounds but iron compounds are white. [2] (b) Iron reacts with dilute hydrochloric acid. Write the word equation for the reaction. + + [1] (c) Fig. 5.1 shows three identical iron nails, each in a different test-tube, A, B and C. A B C oil water Fig. 5.1 Predict in which test-tube the iron nail rusts most quickly. Explain your answer. test-tube … explanation … … … [2] (d) Iron is extracted from iron(III) oxide in a blast furnace. Fe2O3 + 3CO 2Fe + 3CO2 Circle the type of reaction when iron(III) oxide forms iron. combustion oxidation reduction separation [1] (e) Aluminium is extracted by electrolysis. Name the main ore of aluminium. … [1] (f) Part of the reactivity series is shown. sodium magnesium carbon zinc hydrogen copper (i) Use this reactivity series to name: • one metal that must be extracted by electrolysis • one metal that is extracted by heating with carbon. metal extracted by electrolysis … metal extracted by heating with carbon … [2] (ii) Explain why different methods of extraction are needed for the two metals in (f)(i). … … [1] [Total: 10]

10 marks

Mark scheme: 5(a) first and second boxes ticked ; 2 5(b) iron + hydrochloric acid → iron(II) chloride + hydrogen ; 1 5(c) B ; 2 oxygen and water are needed for rusting ; 5(d) reduction ; 1 5(e) bauxite ; 1 5(f)(i) electrolysis: magnesium or sodium ; 2 carbon: zinc or copper ; 5(f)(ii) metals more reactive than carbon are extracted by electrolysis / metals less reactive than carbon can be extracted by 1 heating (with carbon) ;

This question in 0653/32 May/June 2025

6 Scientists are investigating the use of iron as a fuel in cars. Iron reacts with oxygen, as shown in equation 1. This reaction releases energy. The iron oxide formed is converted back to iron, as shown in equation 2. equation 1 … Fe(s) + … O2( … ) 2Fe2O3(s) equation 2 Fe2O3(s) + 3H2(g) 2Fe(s) + 3H2O(l) (a) Balance equation 1 and add the missing state symbol for oxygen. [2] (b) State the name given to a chemical reaction that releases thermal energy. … [1] (c) Use the substances in equation 1 and equation 2 to answer the following questions. (i) Identify the compound that exists as simple molecules. … [1] (ii) Identify the transition element. … [1] (d) Explain why equation 1 shows that iron is oxidised. … … [1] (e) Most cars burn fuels that contain carbon. Explain why using iron as a fuel may cause less harm to the environment than using fuels that contain carbon. … … … … [3] [Total: 9]

9 marks

Mark scheme: 6(a) 4Fe + 3O2 ; 2 (g) ; 6(b) exothermic ; 1 6(c)(i) water / H2O ; 1 6(c)(ii) iron / Fe ; 1 6(d) (Fe / iron) gains oxygen ; 1 6(e) any three from: 3 iron does not produce carbon dioxide / carbon fuels produce carbon dioxide ; iron does not produce carbon monoxide / carbon fuels produce carbon monoxide ; carbon dioxide causes climate change ; carbon monoxide is toxic ; using iron as a fuel only produces water as a waste product ;

This question in 0653/33 May/June 2025