Chemistry 0620/33 October/November 2022: question paper and mark scheme

Question

(a) The structures of seven compounds or elements, A, B, C, D, E, F and G, are shown. A B C D H H H H H H O C O P H C C C H H C C C H H H H H H H H E F G H O H C O H S O O H Answer the following questions about these structures. Each structure may be used once, more than once or not at all. State which structure, A, B, C, D, E, F or G, represents: (i) a compound that contains an atom of an element in Group V of the Periodic Table . …… [1] (ii) an element . …… [1] (iii) a substance that is used for cutting tools . …… [1] (iv) a compound that is a major contributor to climate change . …… [1] (v) a saturated hydrocarbon. . …… [1] (b) Describe how aqueous bromine can be used to distinguish between a saturated hydrocarbon and an unsaturated hydrocarbon. observations with saturated hydrocarbon . …… . …… observations with unsaturated hydrocarbon . …… . …… [2] (c) When a hydrocarbon undergoes incomplete combustion, carbon monoxide is formed. (i) State the meaning of the term incomplete combustion. . …… [1] (ii) Give one adverse effect of carbon monoxide on health. . …… [1] [Total: 9]

Question

(a) The table compares the percentage by mass of the elements in the whole Earth and in the oceans. percentage by mass percentage by mass element in the whole Earth in the oceans calcium 1.1 0.1 chlorine less than 0.01 1.0 hydrogen less than 0.01 11.0 iron 34.6 0.0 magnesium 12.7 1.0 oxygen 29.5 85.0 silicon 15.2 0.0 sodium 0.6 1.0 other elements 6.3 total 100.00 100.00 Answer these questions using only the information in the table. (i) Deduce the percentage by mass of the other elements in the oceans. . …… [1] (ii) State which non-metallic element is present in the whole Earth in the greatest percentage by mass. . …… [1] (iii) Give two major differences in the composition of the whole Earth and of the oceans. 1 . …… . …… 2 . …… . …… [2] (b) Complete the diagram to show the electron arrangement in a chlorine atom. Cl [2] (c) Iron is extracted from iron(III) oxide in a blast furnace. (i) Explain why air is blown into the blast furnace. . …… . …… [1] (ii) In the blast furnace, carbon dioxide reacts with carbon to produce carbon monoxide. Complete the chemical equation for this reaction. CO2 + C → ……CO [1] (iii) Carbon monoxide reduces iron(III) oxide to iron. State the meaning of the term reduction. . …… [1] (iv) When 80 g of iron(III) oxide reacts with excess carbon monoxide, 56 g of iron is produced. Calculate the minimum mass of iron(III) oxide needed to produce 14 g of iron. …… g [1] (d) Steel is an alloy of iron. (i) Choose two substances from the list that are used in the conversion of iron from the blast furnace into steel. calcium oxide carbon dioxide hydrogen nitrogen oxygen silicon(IV) oxide sulfur dioxide 1 . …… 2 . …… [2] (ii) State the meaning of the term alloy. . …… . …… [1] [Total: 13]

Question

This question is about fuels and energy production. (a) The diagram shows the apparatus used to compare the energy released when 100 cm3 of water is heated by burning different liquid fuels, J, K, L and M. thermometer clamp 100 cm3 water copper can liquid fuel All conditions are kept the same apart from the type of fuel and mass of fuel burned. The results are shown. mass of fuel burned increase in temperature fuel /g / °C J 2 4 K 4 8 L 1 3 M 2 5 Deduce which fuel, J, K, L or M, releases the most energy per gram. . …… [1] (b) The fractional distillation of petroleum produces fractions, such as gasoline and diesel, which are used as fuels. (i) Name one other petroleum fraction that is used as a fuel. . …… [1] (ii) State the physical property on which the fractional distillation of petroleum depends. . …… [1] (iii) Bitumen is a fraction of petroleum. Write an X on the diagram to show where bitumen is obtained. lubricating fraction [1] (c) (i) Name a radioactive element that is used as a source of energy in nuclear power stations. . …… [1] (ii) State one other industrial use of radioactive isotopes. . …… [1] [Total: 6]

Question

(a) The table shows some properties of four Group I elements. melting point boiling point hardness element / °C / °C / MPa lithium 181 1342 5.00 sodium 98 …… 0.70 potassium 63 760 0.36 rubidium 39 686 …… (i) Complete the table by predicting: ● the boiling point of sodium ● the hardness of rubidium. [2] (ii) Predict the physical state of potassium at 50 °C. Give a reason for your answer. . …… . …… [2] (b) When a mixture of sodium and sodium hydroxide is heated, sodium oxide and hydrogen are formed. (i) Complete the chemical equation for this reaction. ……Na + 2NaOH → ……Na2O + H2[2] (ii) Describe a test for hydrogen. test . …… observations …… [2] (c) Sodium hydroxide is used to make the red dye alizarin. Alizarin is soluble in ethanol. A crystal of alizarin is placed in a beaker of ethanol. After a few hours, the red colour has spread throughout the beaker. crystal of ethanol alizarin at the start after a few hours Explain these observations using the kinetic particle model. . …… . …… . …… . …… [3] [Total: 11]

Question

This question is about compounds of nitrogen and fertilisers. (a) Ammonium chloride is heated with sodium hydroxide. NH4Cl + NaOH → NH3 + NaCl + H2O Choose from the list the word that describes this reaction. Draw a circle around your answer. addition displacement oxidation reduction[1] (b) Ammonia is manufactured from nitrogen and hydrogen. N2 + 3H2 2NH3 (i) Give the meaning of the symbol . . …… [1] (ii) The nitrogen for this process is obtained from the air. State the percentage of nitrogen in clean, dry air. . …… [1] (c) Fertilisers contain nitrogen. Name two other elements found in most fertilisers that are essential for plant growth. (d) Bacteria in the soil can convert ammonium ions into oxides of nitrogen. Oxides of nitrogen contribute to acid rain. (i) Name one other pollutant in the air that contributes to acid rain. . …… [1] (ii) State one adverse effect of acid rain on buildings. . …… [1] [Total: 7]

Question

This question is about acids, bases and salts. (a) Describe the reaction of excess dilute hydrochloric acid with magnesium and with magnesium carbonate. Give the names of the products and any observations. reaction with magnesium ● products . …… ● observations . …… . …… reaction with magnesium carbonate ● products . …… ● observations . …… . …… [4] (b) (i) Different sized pieces of magnesium react with excess dilute hydrochloric acid. The time taken for each reaction to finish is recorded. The sizes of the pieces of magnesium are: ● large ● small ● very small. Equal masses of magnesium are used in each reaction. All other conditions stay the same. Complete the table by writing the size of the magnesium pieces in the first column. size of time taken for the reaction to finish magnesium pieces /s 30 200 90 [1] (ii) Describe the effect on the time taken for small pieces of magnesium to react with hydrochloric acid of a lower concentration. All other conditions stay the same. . …… [1] (c) (i) Sodium hydroxide is an alkali. State the colour change when excess aqueous sodium hydroxide is added to a solution of methyl orange in acid. (ii) Choose the pH value of an alkali. Draw a circle around your answer. pH 3 pH 5 pH 7 pH 14[1] (d) The salt magnesium chloride can be prepared by reacting hydrochloric acid with magnesium oxide. (i) The method for preparing pure dry crystals of magnesium chloride is given. Complete the missing steps 4 and 6. 1 Add excess magnesium oxide to dilute hydrochloric acid. 2 Warm the mixture to complete the reaction. 3 Filter off the excess magnesium oxide and collect the filtrate. 4 . …… 5 Remove the crystals. 6 . …… [2] (ii) Magnesium oxide is used as a catalyst in some reactions. State the purpose of using a catalyst. . …… [1] [Total: 12]

Question

(a) The structure of an organic compound, S, is shown. H H C H H C C O H C O H (i) On the structure, draw a circle around the carboxylic acid functional group. [1] (ii) Deduce the formula of compound S to show the number of carbon, hydrogen and oxygen atoms. . …… [1] (iii) Compound S is a solid at room temperature. Use the kinetic particle model to describe the arrangement of the particles in a solid. . …… [1] (b) Compound S reacts with ethanol. (i) Draw the structure of ethanol to show all of the atoms and all of the bonds. [1] (ii) Ethanol can be manufactured by fermentation. Describe one other method of manufacturing ethanol. . …… . …… [2] (c) Compound S can be polymerised. (i) State the general name given to the small units that join together to form a polymer. . …… [1] (ii) Name one natural polymer. . …… [1] (iii) Some plastics are non-biodegradable. Describe one pollution problem caused by non-biodegradable plastics. . …… [1] [Total: 9]

Question

This question is about metals. (a) (i) Copper is a transition element. Sodium is an element in Group I of the Periodic Table. Copper is harder than sodium. Give two other ways in which the physical properties of copper differ from the physical properties of sodium. 1 . …… 2 . …… [2] (ii) Give one use of copper. . …… [1] (b) The apparatus used to electroplate a steel spoon with copper is shown. – + steel spoon pure copper rod (i) Label the diagram to show: ● the anode ● the electrolyte. [2] (ii) Describe the observations made during this electroplating at the: steel spoon …… . …… copper rod. …… . …… [2] (c) Deduce the number of electrons and neutrons in one atom of the isotope of copper shown. 29Cu 65 number of electrons . …… number of neutrons …… [2] (d) A compound of copper has the formula K2CuF4. Complete the table to calculate the relative molecular mass of K2CuF4. number relative atom of atoms atomic mass potassium 2 39 2 × 39 = 78 copper 64 fluorine 19 relative molecular mass = …… [2] (e) The table shows the rates of reaction of four metals with steam. metal rate of reaction with steam zinc reacts quickly gold does not react iron reacts slowly lanthanum reacts very quickly Put the four metals in order of their reactivity. Put the least reactive metal first. least reactive most reactive [2] [Total: 13] The Periodic Table of Elements Group I II III IV V VI VII VIII 1 2 H He hydrogen helium Key 1 4 3 4 atomic number 5 6 7 8 9 10 Li Be atomic symbol B C N O F Ne lithium beryllium name boron carbon nitrogen oxygen fluorine neon 7 9 relative atomic mass 11 12 14 16 19 20 11 12 13 14 15 16 17 18 Na Mg Al Si P S Cl Ar sodium magnesium aluminium silicon phosphorus sulfur chlorine argon 23 24 27 28 31 32 35.5 40 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 potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton 39 40 45 48 51 52 55 56 59 59 64 65 70 73 75 79 80 84 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 20 rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon 85 88 89 91 93 96 – 101 103 106 108 112 115 119 122 128 127 131 55 56 57–71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 lanthanoids Cs Ba Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn caesium barium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon 133 137 178 181 184 186 190 192 195 197 201 204 207 209 – – – 87 88 89–103 104 105 106 107 108 109 110 111 112 114 116 actinoids Fr Ra Rf Db Sg Bh Hs Mt Ds Rg Cn Fl Lv francium radium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium flerovium livermorium – – – – – – – – – – – – – 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 lanthanoids La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium 139 140 141 144 – 150 152 157 159 163 165 167 169 173 175 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 actinoids Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium – 232 231 238 – – – – – – – – – – – The volume of one mole of any gas is 24 dm3 at room temperature and pressure (r.t.p.).