Chemistry 0620/23 May/June 2021: question paper and mark scheme

Question

A gas is released at point P in the apparatus shown. P damp universal indicator paper Which gas turns the damp universal indicator paper red most quickly? A ammonia, NH3 B chlorine, Cl 2 C hydrogen chloride, HCl D sulfur dioxide, SO2

Question

A 1 cm3 sample of substance X is taken. This is sample 1. X is then converted to a different physical state and a 1 cm3 sample is taken. This is sample 2. Sample 2 contains more particles in the 1 cm3 than sample 1. Which process caused this increase in the number of particles in 1 cm3? A boiling of liquid X B condensation of gaseous X C evaporation of liquid X D sublimation of solid X

Question

Which statement about paper chromatography is correct? A A solvent is needed to dissolve the paper. B Paper chromatography separates mixtures of solvents. C The solvent should cover the baseline. D The baseline should be drawn in pencil.

Question

Element X has 7 protons. Element Y has 8 more protons than X. Which statement about element Y is correct? A Y has more electron shells than X. B Y has more electrons in its outer shell than X. C Y is in a different group of the Periodic Table from X. D Y is in the same period of the Periodic Table as X.

Question

A covalent molecule Q contains only six shared electrons. What is Q? A ammonia, NH3 B chlorine, Cl 2 C methane, CH4 D water, H2O

Question

Which statement explains why metals are malleable? A The atoms release electrons to become cations. B The electrons are free to move. C The electrons and the cations are attracted to each other. D The layers of ions can slide over each other.

Question

Which statement about isotopes of the same element is correct? A They have different numbers of electrons. B They have different numbers of neutrons. C They have different numbers of protons. D They have the same mass number.

Question

The element silicon has the same structure as diamond. Which statement about silicon is correct? A Every silicon atom is bonded to three other atoms only. B Silicon has a high melting point. C Silicon is a good conductor of electricity. D Silicon is used as a lubricant.

Question

Three ionic compounds of vanadium have the formulae V2O, VCl 2 and V2O3. What is the charge on the vanadium ion in each compound? V2O VCl 2 V2O3 A +1 –2 +2 B +1 +2 +3 C +2 –2 +2 D +2 +2 +3

Question

In separate experiments, electricity was passed through concentrated aqueous sodium chloride and molten lead(II) bromide. What would happen in both experiments? A A halogen would be formed at the anode. B A metal would be formed at the cathode. C Hydrogen would be formed at the anode. D Hydrogen would be formed at the cathode.

Question

The equation for the decomposition of calcium carbonate is shown. CaCO3 → CaO + CO2 What mass of calcium oxide is produced when 10 g of calcium carbonate is heated? A 4.4 g B 5.0 g C 5.6 g D 10.0 g

Question

Gas syringe X contains 100 cm3 of hydrogen bromide gas, HBr. Gas syringe Y contains 100 cm3 of carbon dioxide gas. The volume of each gas is measured at room temperature and pressure. Which statement is correct? A The mass of HBr is less than the mass of CO2. B The number of molecules of HBr equals the number of molecules of CO2. C The gas in syringe X contains more atoms than the gas in syringe Y. D The number of moles of HBr is more than the number of moles of CO2.

Question

Which simple cell produces the most electrical energy? A B V V magnesium zinc iron zinc key V = voltmeter C D V V magnesium copper iron copper

Question

When sulfur is heated it undergoes a ……1…… change as it melts. Further heating causes the sulfur to undergo a ……2…… change and form sulfur dioxide. Which words complete gaps 1 and 2? 1 2 A chemical chemical B chemical physical C physical chemical D physical physical

Question

Four statements about the effect of increasing temperature on a reaction are shown. 1 The activation energy becomes lower. 2 The particles move faster. 3 There are more collisions between reacting particles per second. 4 There are more collisions which have energy greater than the activation energy. Which statements are correct? A 1, 2 and 3 B 1, 3 and 4 C 2, 3 and 4 D 2 and 3 only

Question

An example of a redox reaction is shown. Zn + Cu2+ → Zn2+ + Cu Which statement about the reaction is correct? A Zn is the oxidising agent and it oxidises Cu2+. B Zn is the oxidising agent and it reduces Cu2+. C Zn is the reducing agent and it oxidises Cu2+. D Zn is the reducing agent and it reduces Cu2+.

Question

The equation for the decomposition of hydrogen iodide is shown. 2HI → H2 + I2 Some bond energies are shown. bond energy bond in kJ / mol H–H 440 I–I 150 H–I 300 What is the energy change for the reaction? A –290 kJ / mol B –10 kJ / mol C +10 kJ / mol D +290 kJ / mol

Question

Element X forms an oxide, XO, that neutralises sulfuric acid. Which row describes X and XO? element X nature of oxide, XO A metal acidic B metal basic C non-metal acidic D non-metal basic

Question

Aqueous solutions of sodium sulfate and barium chloride are mixed. Na2SO4(aq) + BaCl 2(aq) → BaSO4(s) + 2NaCl (aq) Which process is used to separate a sample of barium sulfate from the reaction mixture? A precipitation B filtration C evaporation D distillation

Question

Information about element J is shown. ● Its atoms have four electrons in their outer shell. ● It is a non-metal. ● Its oxide has a macromolecular structure. ● It has a high melting point. What is J? A beryllium B carbon C silicon D sulfur

Question

Which property is shown by transition elements? A low density B low melting point C variable oxidation state D white compounds

Question

Helium and neon exist as monoatomic gases at room temperature and pressure. statement 1 Helium and neon have eight electrons in their outer shell. statement 2 Helium and neon are unreactive. Which option is correct? A Statement 1 and statement 2 are incorrect. B Statement 1 is correct and explains statement 2. C Statement 1 is correct, but does not explain statement 2. D Statement 1 is incorrect, but statement 2 is correct.

Question

What are possible effects of an inadequate water supply during a drought? 1 crop failure 2 wastage of water 3 human disease 4 death of farm animals A 1, 2 and 3 B 1 and 2 only C 1, 3 and 4 D 3 and 4 only

Question

Which statement explains why galvanising prevents iron from rusting? A Zinc is more reactive than iron and corrodes in preference to iron. B Zinc is more reactive than iron and loses electrons less easily than iron. C Zinc is less reactive than iron and corrodes in preference to iron. D Zinc is less reactive than iron and loses electrons more easily than iron.

Question

Some metal nitrates and carbonates decompose when heated strongly. Metal Q has a nitrate that decomposes to give a salt and a colourless gas only. The carbonate of metal Q does not decompose when heated with a Bunsen burner. What is metal Q? A calcium B copper C sodium D zinc

Question

Which compounds are released by the extraction of zinc from zinc blende and by respiration? extraction of zinc respiration A CO2 and SO2 CO2 only B CO2 and SO2 CO2 and H2O C CO2 only CO2 only D CO2 only CO2 and H2O

Question

Which gas is an air pollutant that causes acid rain? A argon B carbon monoxide C methane D nitrogen dioxide

Question

Ammonia is made from nitrogen and hydrogen. The equation for the reaction is shown. N2(g) + 3H2(g) 2NH3(g) The forward reaction is exothermic. Which conditions give the greatest equilibrium yield of ammonia? temperature pressure / °C / atm A 200 15 B 200 150 C 500 15 D 500 150

Question

Which reaction does not occur during the extraction of iron from hematite in a blast furnace? A C + O2 → CO2 B CaO + SiO2 → CaSiO3 C CO2 + C → 2CO D 4Fe + 3O2 → 2Fe2O3

Question

Which substance is used as a catalyst in the manufacture of sulfuric acid by the Contact process? A iron B nickel C phosphoric acid D vanadium(V) oxide

Question

Metal X is a good conductor of electricity and is used for electrical wiring. Metal Y is used to make an alloy which is resistant to corrosion and is used to make cutlery. Metal Z is light and strong and is used in the manufacture of aircraft. What are X, Y and Z? X Y Z A aluminium iron copper B copper iron aluminium C aluminium copper iron D copper aluminium iron

Question

The formulae of two compounds of manganese are MnO2 and KMnO4. In these two compounds the oxidation state of potassium is +1 and the oxidation state of oxygen is –2. What are the oxidation states of manganese in each of these two compounds? MnO2 KMnO4 A +2 +3 B +2 +7 C +4 +3 D +4 +7

Question

Which statement about calcium carbonate is correct? A It is made by the thermal decomposition of limestone. B It is used to neutralise alkaline soils. C It is a reactant in the test for carbon dioxide. D It is used to remove impurities in iron extraction.

Question

Ethanol is reacted with acidified potassium manganate(VII). Which row describes the type of reaction and the type of organic compound formed? type of reaction organic compound A oxidation carboxylic acid B oxidation alkene C dehydration carboxylic acid D dehydration alkene

Question

The diagrams show the structural formulae of four compounds. 1 2 H H H H H H H H H C C C C C H H C C C C C H H H H H H H H H H H C H H 3 4 H H H H H H H H H H C C C C H H C C C C C H H H H H H H H H C H H C H H H Which two compounds are structural isomers? A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

Question

Which statement about alkanes is correct? A They burn in oxygen. B They contain carbon, hydrogen and oxygen atoms. C They contain double bonds. D They contain ionic bonds.

Question

How much hydrogen is needed to react completely with 0.02 moles of butene to make butane? A 0.24 dm3 B 0.48 dm3 C 0.96 dm3 D 1.20 dm3

Question

What is an advantage of the fermentation process for producing ethanol compared with the catalytic addition of steam to ethene? A Fermentation requires less heat energy. B Ethanol from fermentation needs to be distilled. C Raw materials for fermentation are non-renewable. D The fermentation process is carried out in batches rather than continuously.

Question

The structure of a synthetic polymer is shown. O O O O O C C N N C C N N C H H H H The structure shows that it is a ……1…… . It is formed by ……2…… polymerisation. Which words complete gaps 1 and 2? 1 2 A polyamide addition B polyamide condensation C polyester addition D polyester condensation

Question

Which substance is a natural polymer? A ethene B Terylene C nylon D protein 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 85 88 89 91 93 96 – 101 103 106 108 112 115 119 122 128 127 131 16 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.).