Chemistry 0620/22 May/June 2020: question paper and mark scheme

Question

A mixture of ice and water is left to stand and the ice melts. Which row describes what happens as the ice is melting? temperature of mixture energy changes A increases average kinetic energy of particles increases B increases energy is used to overcome attractive forces C stays the same average kinetic energy of particles increases D stays the same energy is used to overcome attractive forces

Question

Which piece of apparatus is used to measure 25.0 cm3 of aqueous sodium hydroxide? A B C D

Question

Paper chromatography is used to determine the Rf values for four different food colourings. Which food colouring has an Rf value of 0.6? solvent front 25 20 15 distance / cm 10 5 baseline 0 A B C D

Question

The diagram shows the electronic structure of a particle with a nucleon number (mass number) of 40. e e e e e e e e e e e 40 e e e e e e e The table shows the suggestions that three students, 1, 2 and 3, made to identify the particle. student 1 2 3 particle Ar Cl Ca2+ Which students are correct? A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3

Question

The electronic structures of two atoms, P and Q, are shown. P Q P and Q combine together to form a compound. What is the type of bonding in the compound and what is the formula of the compound? type of bonding formula A ionic PQ B ionic PQ2 C covalent PQ2 D covalent PQ

Question

Which statement about the structure of a metal explains why metals are malleable? A The electrons can move freely throughout the lattice. B The layers of metal ions can slide over each other. C The metal ions are positively charged. D There is a strong force of attraction between the metal ions and the electrons.

Question

The bonding, structure and melting point of sodium chloride and sulfur dichloride are shown. compound bonding structure melting point / °C sodium chloride ionic giant lattice 801 sulfur dichloride covalent simple molecular –121 Why does sulfur dichloride have a lower melting point than sodium chloride? A The covalent bonds in sulfur dichloride are weaker than the attractive forces between molecules in sodium chloride. B The covalent bonds in sulfur dichloride are weaker than the ionic bonds in sodium chloride. C The attractive forces between molecules in sulfur dichloride are weaker than the attractive forces between molecules in sodium chloride. D The attractive forces between molecules in sulfur dichloride are weaker than the ionic bonds in sodium chloride.

Question

Lead(II) nitrate, Pb(NO3)2, reacts with potassium iodide, KI, to form a yellow precipitate, PbI2, and a soluble salt, KNO3. What is the equation for the reaction? A Pb(NO3)2 + KI → PbI2 + KNO3 B Pb(NO3)2 + 2KI → PbI2 + KNO3 C 2Pb(NO3)2 + 2KI → PbI2 + 2KNO3 D Pb(NO3)2 + 2KI → PbI2 + 2KNO3

Question

The Haber process is a reversible reaction. N2(g) + 3H2(g) 2NH3(g) The reaction has a 30% yield of ammonia. Which volume of ammonia gas, NH3, measured at room temperature and pressure, is obtained by reacting 0.75 moles of hydrogen with excess nitrogen? A 3600 cm3 B 5400 cm3 C 12 000 cm3 D 18 000 cm3

Question

Electrolytes can be broken down by electrolysis. Which rows are correct for each electrolyte? reaction product electrolyte at cathode at anode 1 dilute aqueous sodium chloride 2H+ + 2e– → H2 oxygen + – 2 concentrated hydrochloric acid 2H + 2e → H2 chlorine 2– – 3 molten aluminium oxide 2O → O2 + 4e aluminium 4 concentrated aqueous sodium bromide Na+ + e– → Na bromine A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

Question

The electrolysis of aqueous copper(II) sulfate, using inert electrodes, is shown. + – aqueous copper(II) sulfate Which statement about a reaction at an electrode is correct? A Copper ions gain electrons at the negative electrode. B Copper ions gain electrons at the positive electrode. C Hydrogen ions gain electrons at the negative electrode. D Hydrogen ions gain electrons at the positive electrode.

Question

Methane burns in excess oxygen. The equation is shown. CH4(g) + 2O2(g) → CO2(g) + 2H2O(g) Bond energies are shown. bond energy bond / kJ mol–1 C=O 805 C–H 410 O=O 496 O–H 460 What is the energy change for the reaction? A (4 × 410 + 2 × 496) – (2 × 805 + 4 × 460) B (2 × 805 + 2 × 460) – (410 + 2 × 496) C (410 + 2 × 496) – (805 + 2 × 460) D (410 + 496) – (805 + 460)

Question

Which statements about hydrogen fuel cells are correct? 1 Water is formed as the only waste product. 2 Both water and carbon dioxide are formed as waste products. 3 The overall reaction is 2H2 + O2 → 2H2O. 4 The overall reaction is endothermic. A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

Question

Which list contains only chemical changes? A melting, evaporating, dissolving B rusting, freezing, subliming C neutralisation, polymerisation, combustion D boiling, condensing, distillation

Question

The results of adding excess marble chips (calcium carbonate) to hydrochloric acid at 50 °C and at 30 °C are shown. Only the temperature is changed. 50 °C volume of 30 °C carbon dioxide given off / cm3 0 0 time / s Which row describes the reacting particles at 30 °C compared to those at 50 °C? collision rate collision energy A higher higher B higher lower C lower higher D lower lower

Question

Methane reacts with steam and an equilibrium is reached. CH4(g) + H2O(g) CO(g) + 3H2(g) The forward reaction is endothermic. Which row shows how the amount of hydrogen at equilibrium changes when the pressure or temperature is changed as indicated? change in change in amount of temperature pressure hydrogen A decrease no change increase B increase no change decrease C no change increase decrease D no change decrease decrease

Question

When aqueous iron(III) chloride is added to aqueous potassium iodide a chemical reaction occurs and iodine is formed. Which statement is correct? A Iodide ions are oxidised, they gain electrons in this reaction. B Iodide ions are oxidised, they lose electrons in this reaction. C Iron(III) chloride is oxidised in this reaction. D Neither iodide ions nor iron(III) chloride is oxidised in this reaction.

Question

The graph shows how the pH of a solution changes as an acid is added to an alkali. acid + alkali → salt + water Which letter represents the area of the graph where both acid and salt are present? A 14 B C pH 7 D 0 volume of acid added

Question

Which statement describes a weak acid? A It is a proton acceptor and is fully ionised in aqueous solution. B It is a proton acceptor and is partially ionised in aqueous solution. C It is a proton donor and is fully ionised in aqueous solution. D It is a proton donor and is partially ionised in aqueous solution.

Question

The apparatus shown is used to prepare aqueous copper(II) sulfate. filter paper stirrer excess of solid X solid X Y aqueous copper(II) sulfate heat What are X and Y? X Y A copper aqueous iron(II) sulfate B copper(II) chloride dilute sulfuric acid C copper(II) oxide dilute sulfuric acid D sulfur aqueous copper(II) chloride

Question

Which process is not used in the preparation of an insoluble salt? A filtration B washing C crystallisation D drying

Question

Which statement about Group I and Group VII elements is correct? A Group VII elements are monoatomic non-metals. B Lithium is more reactive with water than caesium. C The melting points of Group I metals increase down the group. D Potassium bromide reacts with chlorine to produce an orange solution.

Question

The properties of the element titanium, Ti, can be predicted from its position in the Periodic Table. Which row identifies the properties of titanium? can be used conducts electricity forms coloured has low density as a catalyst when solid compounds A B C D

Question

Which diagram shows a mixture of noble gases? A B C D

Question

Which property is shown by all metals? A They are extracted from their ores by heating with carbon. B They conduct electricity. C They form acidic oxides. D They react with hydrochloric acid to form hydrogen.

Question

Many metal carbonates decompose when they are heated. Which row describes what happens when potassium carbonate, calcium carbonate and copper(II) carbonate are heated using a Bunsen burner? decomposes does not decompose at decomposes easily with difficulty Bunsen temperatures A calcium carbonate copper(II) carbonate potassium carbonate B copper(II) carbonate calcium carbonate potassium carbonate C copper(II) carbonate potassium carbonate calcium carbonate D potassium carbonate calcium carbonate copper(II) carbonate

Question

Molten iron from the blast furnace contains impurities. The process of turning the impure iron into steel involves blowing oxygen into the molten iron and adding calcium oxide. What are the reasons for blowing in oxygen and adding calcium oxide? blowing in oxygen adding calcium oxide A carbon is removed by reacting with oxygen reacts with acidic impurities making slag B carbon is removed by reacting with oxygen reacts with slag and so removes it C iron reacts with the oxygen reacts with acidic impurities making slag D iron reacts with the oxygen reacts with slag and so removes it

Question

Four iron nails are added to four different metal sulfate solutions. In which solution does a displacement reaction occur? A copper(II) sulfate B magnesium sulfate C sodium sulfate D zinc sulfate

Question

Which statement about pure water is not correct? A It condenses at 100 °C. B It freezes at 0 °C. C It turns cobalt(II) chloride paper blue. D It turns anhydrous copper(II) sulfate blue.

Question

Three processes in the carbon cycle are shown. 1 Methane reacts with oxygen producing carbon dioxide and water. 2 Carbon dioxide and water are absorbed and used by plants to make oxygen. 3 Oxygen is used by living things to release energy. Which processes have taken place? 1 2 3 A combustion photosynthesis respiration B combustion respiration photosynthesis C photosynthesis combustion respiration D respiration photosynthesis combustion

Question

In the Haber process, nitrogen and hydrogen are reacted to make ammonia. N2(g) + 3H2(g) 2NH3(g) The forward reaction is exothermic. Which conditions produce the maximum yield of ammonia? pressure temperature A high high B high low C low high D low low

Question

Which process, used to prevent iron from rusting, involves sacrificial protection? A alloying B electroplating C galvanising D painting

Question

A student suggests three uses of calcium carbonate (limestone). 1 manufacture of cement 2 manufacture of iron 3 treating alkaline soils Which suggestions are correct? A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3

Question

One of the reactions used in the manufacture of sulfuric acid is shown. 2SO2 + O2 2SO3 Which catalyst is used to increase the rate of this reaction? A iron B manganese(IV) oxide C vanadium(V) oxide D nickel

Question

Ethanol is made on an industrial scale by the fermentation of sugars or by the reaction of ethene with steam in the presence of a suitable catalyst. What is a disadvantage of making ethanol from ethene rather than by fermentation? A A continuous production process is used. B A non-renewable raw material is used. C The product is very pure. D The rate of reaction is very high.

Question

Which statement about compounds in the same homologous series is correct? A They have the same chemical properties because they have the same number of carbon atoms. B They have the same physical properties because they have the same number of carbon atoms. C They have different chemical properties because they have different numbers of carbon atoms. D They have different physical properties because they have different numbers of carbon atoms.

Question

Increasing the number of atoms in one molecule of a hydrocarbon increases the amount of energy released when it burns. What is the correct order? less energy more energy released released A ethene ethane methane B ethene methane ethane C methane ethane ethene D methane ethene ethane

Question

An organic compound, P, reacts with zinc to produce a gas, Q. What are P and Q? P Q A ethanoic acid carbon dioxide B ethanoic acid hydrogen C ethanol carbon dioxide D ethanol hydrogen

Question

Alkanes undergo substitution reactions in the presence of UV light. Which equation represents a substitution reaction of ethane? A C2H6 + Cl 2 → C2H4 + 2HCl B C2H6 + Cl 2 → C2H5Cl + HCl C C2H6 + Cl 2 → C2H4Cl 2 + H2 D C2H6 + HCl → C2H5Cl + H2

Question

Which substances are natural polymers? 1 proteins 2 carbohydrates 3 nylon 4 poly(ethene) A 1 and 2 B 1 and 3 C 2 and 3 D 3 and 4 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 rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon 16 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.).