Chemistry 0620/21 May/June 2024: question paper and mark scheme

Question

A gas is heated. The pressure is kept constant. Which statement describes the behaviour of the particles in the gas? A The particles move faster and become closer together. B The particles move faster and become further apart. C The particles move more slowly and become closer together. D The particles move more slowly and become further apart.

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 energy change mixture A increases average kinetic energy of particles decreases B increases energy is used to overcome attractive forces C stays the same average kinetic energy of particles decreases D stays the same energy is used to overcome attractive forces

Question

Hydrogen chloride gas [Mr: HCl, 36.5] is released at P in the apparatus shown. The universal indicator paper turns red after 38 s. P universal indicator paper The experiment is repeated using sulfur dioxide gas [Mr: SO2, 64]. What is the result for sulfur dioxide gas? universal time for indicator universal indicator paper paper turns to change colour / s A blue 26 B blue 51 C red 26 D red 51

Question

Four statements about atoms are listed. 1 The centre of an atom is positively charged. 2 Protons and electrons are located in the nucleus. 3 Protons and electrons have the same mass. 4 Most of the mass of an atom is in the nucleus. Which statements are correct? A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

Question

The electronic configurations of two elements are given. element L: 2,8,8,1 element M: 2,8,4 Which row identifies the group number and the period number for element L and element M? element L element M group number period number group number period number A I 4 IV 3 B I 4 III 4 C IV 1 III 4 D IV 1 IV 3

Question

Which statement explains why isotopes of the same element have the same chemical properties? A They have different numbers of protons in their nucleus. B They have different numbers of neutrons in their nucleus. C They have the same electronic configuration. D They have the same number of electrons as protons.

Question

Which statements about potassium chloride are correct? 1 It conducts electricity when solid because its ions are free to move. 2 It has a high melting point because it has strong intermolecular forces. 3 Its structure is a giant lattice of alternating positive and negative ions. 4 It is soluble in water. A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

Question

How many electrons are shared in one molecule of nitrogen and in one molecule of ethene? nitrogen ethene A 2 12 B 2 8 C 6 12 D 6 8

Question

What is the total number of electrons in one molecule of ammonia, NH3? A 6 B 8 C 10 D 11

Question

When heated, copper(II) oxide, CuO, reacts with ammonia, NH3. 3CuO + 2NH3 → 3Cu + N2 + 3H2O 8.5 g of ammonia reacts with an excess of copper(II) oxide to produce 26.4 g of copper. What is the percentage yield of copper in this reaction? A 27.5% B 32.2% C 55.0% D 82.5%

Question

What is the empirical formula of ethanoic acid? A CHO B CH2O C C2H2O D C2H4O2

Question

Magnesium chloride, MgCl 2, contains magnesium ions and chloride ions. How many chloride ions are present in two moles of magnesium chloride? 23 A 6.02 × 10 24 B 1.204 × 10 24 C 2.408 × 10 24 D 3.612 × 10

Question

A metal object is electroplated with copper. One electrode is the metal object and the other electrode is copper. The electrolyte is aqueous copper(II) sulfate. Which row shows the ionic half-equation for the reaction at the anode and the observation of the electrolyte? anode electrolyte 2+ – A Cu + 2e → Cu blue colour fades 2+ – B Cu + 2e → Cu blue colour does not change 2+ – C Cu → Cu + 2e blue colour fades 2+ – D Cu → Cu + 2e blue colour does not change

Question

Which statement about electrolysis is correct? A Chemical energy is converted to electrical energy. B Electrons flow through the electrolyte. C Ionic compounds are broken down. D Metals are formed at the positive electrode.

Question

The reaction between hydrogen and oxygen releases 486 kJ / mol of energy. 2H2(g) + O2(g) → 2H2O(g) The bond energy of H–H is 436 kJ / mol and that of H–O is 464 kJ / mol. What is the bond energy of O=O? A 430 kJ / mol B 458 kJ / mol C 498 kJ / mol D 984 kJ / mol

Question

Which reaction pathway diagram shows the reaction that will give out the most energy? The scale on the y-axis is the same in each diagram. A B reactants products energy energy products reactants progress of reaction progress of reaction C D products reactants energy energy reactants products progress of reaction progress of reaction

Question

When calcium carbonate is heated strongly, a gas is given off. Which word describes this change? A chemical B exothermic C physical D reduction

Question

Powdered magnesium carbonate is added to excess dilute hydrochloric acid. The total volume of gas produced is measured over time. A graph of the results is shown. 300 200 total volume of gas produced / cm3 100 0 0 25 50 75 100 125 150 175 200 time / s The experiment is repeated but the concentration of the hydrochloric acid is doubled. All other conditions are kept the same. Which statements about the second experiment are correct? 3 1 The final volume of gas is 360 cm . 2 The reaction finishes before 90 seconds. 3 The activation energy of the reaction is lower. A 1 and 2 B 1 and 3 C 2 and 3 D 2 only

Question

Which statements explain why increasing the temperature changes the rate of a chemical reaction? 1 It increases the activation energy. 2 It increases the frequency of collisions between the reacting particles. 3 It increases the kinetic energy of the reacting particles. 4 It increases the number of particles per unit volume. A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

Question

Hydrogen is made by reacting carbon with steam. The equation for the reaction is shown. C(s) + H2O(g) ⇌ H2(g) + CO(g) The forward reaction is endothermic. Which row describes changes in the pressure and the temperature that will both shift the position of equilibrium to the right? pressure temperature A decrease decrease B decrease increase C increase decrease D increase increase

Question

Which row shows the conditions used for the conversion of sulfur dioxide to sulfur trioxide in the Contact process? pressure / atm temperature / °C catalyst A 250 200 vanadium(V) oxide B 2 450 vanadium(V) oxide C 250 200 iron D 2 450 iron

Question

The equation for the reaction of magnesium with carbon dioxide is shown. 2Mg + CO2 → 2MgO + C Which statement about this reaction is correct? A Magnesium is oxidised and carbon dioxide is reduced. B Magnesium is reduced and carbon dioxide is oxidised. C Magnesium and carbon dioxide are both oxidised. D Magnesium and carbon dioxide are neither oxidised nor reduced.

Question

Chlorine displaces bromine from aqueous potassium bromide. The ionic equation for the reaction is shown. – – Cl 2 + 2Br → 2Cl + Br2 Which statement about this reaction is correct? A Bromide ions act as an oxidising agent. B Bromide ions are oxidised as electrons are lost. C Chlorine acts as a reducing agent. D Chlorine is reduced as electrons are lost.

Question

Which gas is produced when ammonium chloride is warmed with aqueous sodium hydroxide? A ammonia B chlorine C hydrogen D nitrogen

Question

Which equation represents a solution of ethanoic acid in water? – + A HCOOH(aq) ⇌ HCOO (aq) + H (aq) – + B HCOOH(aq) → HCOO (aq) + H (aq) – + C CH3COOH(aq) ⇌ CH3COO (aq) + H (aq) – + D CH3COOH(aq) → CH3COO (aq) + H (aq)

Question

Four statements about the reactions of oxides with dilute hydrochloric acid and with aqueous sodium hydroxide are listed. 1 Aluminium oxide reacts with both dilute hydrochloric acid and aqueous sodium hydroxide. 2 Calcium oxide reacts with both dilute hydrochloric acid and aqueous sodium hydroxide. 3 Copper(II) oxide reacts with dilute hydrochloric acid but not with aqueous sodium hydroxide. 4 Sulfur dioxide does not react with either dilute hydrochloric acid or aqueous sodium hydroxide. Which statements are correct? A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4

Question

Which statement about elements in Period 3 of the Periodic Table is correct? A Aluminium is a non-metal in Group III. B Argon is in Group VIII and has eight electrons in its outer electron shell. C Magnesium is in Group II and has three electrons in its outer electron shell. D Sulfur is a metal in Group VI.

Question

Which row describes the structure of Group VII elements and the trend in their reactivity down the group? reactivity down structure Group VII A diatomic increases B diatomic decreases C monatomic increases D monatomic decreases

Question

Some information about four elements, P, Q, R and S, is shown. melting point density colour of 3 in °C in g / cm chloride P 1247 7.43 pink Q 1410 2.33 white R 1910 6.11 purple S 115 2.07 red Which elements are transition elements? A P and R B P and S C Q and R D R and S

Question

Propanoic acid is a carboxylic acid. It has similar chemical properties to ethanoic acid. Which statements are correct? 1 Aqueous propanoic acid is a weaker acid than dilute hydrochloric acid. 2 Propanoic acid partially ionises in aqueous solution. 3 Propanoic acid reacts with ethanol to form propyl ethanoate. A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Question

Iron rusts in the presence of oxygen and water. Which statements about the rusting of iron are correct? 1 Anhydrous iron(II) oxide is produced when iron rusts. 2 Iron rusts more quickly when attached to a piece of zinc. 3 Coating the iron with plastic prevents the iron from rusting. 4 Iron loses electrons when it rusts. A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

Question

An iron nail is added to aqueous copper(II) sulfate and a different iron nail is added to aqueous magnesium sulfate. The results are shown. experiment result iron nail in nail is coated with a brown solid aqueous copper(II) sulfate iron nail in no reaction aqueous magnesium sulfate Which statement is correct? A Copper atoms are oxidised more easily than magnesium atoms. B Copper atoms are reduced more easily than iron ions. C Iron atoms are oxidised more easily than copper atoms. D Iron atoms are reduced more easily than copper ions.

Question

Which pollutant leads to the deoxygenation of water in ponds and lakes? A fertilisers containing nitrates and phosphates B toxic metal compounds C combustion products of fossil fuels D acid rain

Question

Which statement identifies a sample of water as pure? A It melts at room temperature. B It turns anhydrous copper(II) sulfate blue. C It turns hydrated cobalt(II) chloride from blue to pink. D It boils at 100 °C.

Question

Oxides of nitrogen are produced by car engines. In a catalytic converter oxides of nitrogen are removed by reacting them with compound X. Which row describes the type of reaction oxides of nitrogen undergo and identifies compound X? type of reaction compound X A oxidation carbon dioxide B oxidation carbon monoxide C reduction carbon dioxide D reduction carbon monoxide

Question

What is a disadvantage of producing ethanol using the catalytic addition of steam to ethene? A the energy cost is low B the process is continuous C the process uses a non-renewable raw material D the ethanol is pure

Question

Which statement about the polymer PET is correct? A It can be broken down into its monomers and re-polymerised. B It is an addition polymer. C It is a polyamide. D It is made from amino acid monomers.

Question

The formulae of five compounds are listed. 1 C4H10 2 C2H5OH 3 C4H9OH 4 C4H9COOH 5 C5H11OH Which compounds are in the same homologous series? A 1, 3 and 4 B 2, 3 and 5 C 3 and 4 only D 3 and 5 only

Question

Propane reacts with chlorine. Which statements about this reaction are correct? 1 Ultraviolet light is used to provide the activation energy. 2 Propane undergoes an addition reaction. 3 One of the products is CH3CH2Cl . 4 One of the products is HCl . A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

Question

Which statement about chromatography is correct? A It is not possible for two different substances to have the same Rf value. B It is only possible to use chromatography on substances which have a colour. C It is possible to use chromatography on colourless substances using a locating agent. D The Rf value of a substance = 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 06_0620_21_2024_1.13 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 89–103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 actinoids Fr Ra Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og francium radium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson – – – – – – – – – – – – – – – – – 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.).