Chemistry 0620/23 October/November 2022: question paper and mark scheme

Question

Which gas diffuses the most slowly? A CH4 B CO2 C H2 D NH3

Question

The chromatogram from four different substances is shown. Which pure substance has the largest Rf value? A B C D

Question

The structure of sodium chloride can be represented as shown. X Y What are X and Y? X Y A metal atom non-metal atom B negative ion electron C positive ion negative ion D positive ion electron

Question

Which two particles have the same electronic structure? A C and O2– B F – and Na C K+ and S2– D Mg and Na+

Question

Which statements about isotopes of the same element are correct? 1 They are atoms which have the same chemical properties because they have the same number of electrons in their outer shell. 2 They are atoms which have the same number of electrons and neutrons but different numbers of protons. 3 They are atoms which have the same number of electrons and protons but different numbers of neutrons. A 1 and 2 B 1 and 3 C 2 only D 3 only

Question

What is the total number of shared electrons in a molecule of methanol, CH3OH? A 4 B 5 C 8 D 10

Question

Which row about the structures and uses of diamond and graphite is correct? structure use A diamond has a giant covalent structure diamond is used to make electrodes B diamond has a simple covalent structure diamond is used to make cutting tools C graphite has a giant covalent structure graphite is used as a lubricant D graphite has a simple covalent structure graphite is used to make cutting tools

Question

Caffeine is a stimulant found in coffee. O CH3 H 3C C N N C C H C C N O N CH3 caffeine Which formula represents caffeine? A C7H10N4O2 B C8H10N3O2 C C8H10N4O2 D C8H11N4O2

Question

The equation for the reaction between hydrogen sulfide, H2S, and oxygen is shown. 2H2S + 3O2 → 2SO2 + 2H2O Which mass of oxygen is required to react with 5.1 g of hydrogen sulfide? A 2.4 g B 4.8 g C 7.2 g D 14.4 g

Question

Which apparatus is used to plate a nickel object with silver? A B power power supply supply silver + – nickel nickel + – silver object object silver nitrate silver nitrate solution solution C D power power supply supply silver + – nickel nickel + – silver object object nickel nitrate nickel nitrate solution solution

Question

When an acid is added to an alkali, the temperature of the reaction mixture rises. Which words describe this reaction? A decomposition and endothermic B decomposition and exothermic C neutralisation and endothermic D neutralisation and exothermic

Question

Some properties of four fuels are shown. Which fuel is a gas at room temperature and makes two products when it burns in a plentiful supply of air? melting point boiling point fuel formula / °C / °C A hydrogen H2 –259 –253 B methane CH4 –182 –164 C octane C8H18 –57 126 D wax C31H64 60 400

Question

Dinitrogen tetroxide, N2O4, is converted into nitrogen dioxide, NO2, in a reversible reaction. N2O4(g) 2NO2(g) The forward reaction is endothermic. Which conditions give the highest equilibrium yield of nitrogen dioxide? pressure temperature / atmospheres A 2 high B 2 low C 50 high D 50 low

Question

Dilute hydrochloric acid is reacted with excess calcium carbonate and the total volume of gas is measured at regular intervals. The results are shown by line W on the graph. The experiment is repeated but with one change. The results of the second experiment are shown by line X on the graph. W volume of X gas collected 0 0 time Which change is made in the second experiment? A A catalyst is added. B The calcium carbonate is broken into smaller pieces. C The concentration of the dilute hydrochloric acid is increased. D The temperature of the dilute hydrochloric acid is decreased.

Question

When hydrated copper(II) sulfate is heated, it produces white copper(II) sulfate. When water is added, the white copper(II) sulfate turns blue. Which type of reaction is shown by these observations? A decomposition B displacement C redox D reversible

Question

When magnesium is heated with zinc oxide a reaction occurs. The equation is shown. Mg + ZnO → MgO + Zn Which substance is oxidised? A magnesium B magnesium oxide C zinc D zinc oxide

Question

The equation for the reaction between ethene and hydrogen is shown. CH2=CH2(g) + H2(g) → CH3–CH3(g) The bond energies are shown. bond energy bond in kJ / mol C=C 612 H–H 436 C–C 348 C–H 416 What is the overall energy change during this reaction? A –284 kJ / mol B –132 kJ / mol C +132 kJ / mol D +284 kJ / mol

Question

Ethanoic acid reacts with water to produce an acidic solution. Which row describes the roles of ethanoic acid and water in this reaction? ethanoic acid water A accepts a proton donates a proton B accepts an electron donates an electron C donates a proton accepts a proton D donates an electron accepts an electron

Question

Tests are done on an aqueous solution. a few drops of aqueous aqueous sodium hydroxide test sodium hydroxide are added is added in excess precipitate dissolves to observation white precipitate give a colourless solution Which cations produce these observations? 1 aluminium, Al 3+ 2 calcium, Ca2+ 3 zinc, Zn2+ A 1 and 2 B 1 and 3 C 1 only D 2 and 3

Question

Ammonia, NH3, dissolves in water to form a dilute solution of ammonium hydroxide, NH4OH. The reaction is reversible and exists as an equilibrium mixture. NH3(g) + H2O(l) NH4+(aq) + OH–(aq) Which statement about the mixture is correct? A All of the ammonia and water molecules have turned into ions. B The ammonia and water molecules have stopped changing into ions. C The concentrations of the ammonia molecules and ammonium ions are always equal. D The rate of the formation of ammonia molecules is equal to the rate of formation of the ammonium ions.

Question

Elements E and F are in Group I of the Periodic Table. E has a higher melting point than F. Elements J and L are in Group VII of the Periodic Table. J has a higher density than L. Which elements have the highest atomic numbers in each group? A E and J B E and L C F and J D F and L

Question

Which metal forms ions with one oxidation state? A aluminium B chromium C copper D iron

Question

How does the nature of the oxides change across Period 3 from sodium to chlorine? A basic → amphoteric → acidic B basic → acidic → amphoteric C amphoteric → basic → acidic D acidic → amphoteric → basic

Question

Zinc is a metal with a boiling point of 907 °C. Two methods of making zinc are shown. heat with carbon at 1000 qC zinc method 1 zinc ore zinc oxide method 2 zinc sulfate zinc dissolve solution electrolysis in dilute at 35 qC sulfuric acid Which statement is correct? A Carbon oxidises zinc oxide in method 1. B Zinc vapour is produced in both methods. C Zinc is produced at the anode in method 2. D Zinc compounds are reduced in both methods.

Question

Which statement about the reactions of metals is correct? A Iron and carbon dioxide are produced when iron(III) oxide is heated with carbon. B Magnesium reacts with dilute hydrochloric acid producing hydrogen and chlorine. C Potassium reacts vigorously with water producing hydrogen and an acidic solution. D Zinc reacts with dilute sulfuric acid producing sulfur dioxide. 26 12.4 g of copper(II) carbonate is heated in a test-tube. Only 50% is decomposed. [Mr: CuCO3, 124; CuO, 80] What will be the final mass of the substances in the test-tube? A 9.4 g B 9.8 g C 10.2 g D 10.6 g

Question

In the question paper above.

Question

Which statement about the manufacture of ammonia is correct? A Ammonia is manufactured by heating hydrogen and nitrogen at 50 °C and 1.0 atm. B Ammonia is obtained by heating hydrogen and nitrogen in the Contact process. C Hydrogen for the manufacture of ammonia is extracted from air. D The reaction between hydrogen and nitrogen to form ammonia is reversible.

Question

The diagram shows a stage in the purification of dirty water. dirty water sand pot with holes fine gravel in bottom coarse gravel Which process does this apparatus show? A chlorination B condensation C distillation D filtration

Question

Which substance in polluted air damages stonework and kills trees? A carbon dioxide B carbon monoxide C lead compounds D sulfur dioxide

Question

Petrol-fuelled cars produce oxides of nitrogen. Which statement explains how oxides of nitrogen are formed? A In the catalytic converter, the elements nitrogen and oxygen combine. B Oxygen and nitrogen compounds in petrol combine in the car engine. C The high temperatures in the engine provide oxygen and nitrogen with the activation energy needed to react. D In the car engine, nitrogen compounds in petrol combine with oxygen.

Question

The scheme shows four stages in the conversion of sulfur to sulfuric acid. In which stage is a catalyst used? stage A sulfur stage B sulfur sulfur air dioxide air trioxide concentrated stage C sulfuric acid concentrated stage D oleum sulfuric acid water

Question

Which element has an oxide that is used as a food preservative? A helium B hydrogen C iron D sulfur

Question

Which substance gives off carbon dioxide on heating? A lime B limestone C limewater D slaked lime

Question

Which formula represents ethyl butanoate? A CH3CH2CH2COOCH2CH3 B CH3COOCH2CH2CH2CH3 C CH3CH2CH2CH2COOCH2CH3 D CH3CH2COOCH2CH2CH2CH3

Question

Methanol, CH3OH, is a member of the homologous series of alcohols. What is the formula of the alcohol in the same homologous series which contains three carbon atoms? A C3H5OH B C3H6OH C C3H7OH D C3H8OH

Question

Which type of compound reacts with hydrogen in an addition reaction? A alkanes B alkenes C alcohols D carboxylic acids

Question

The equation for the reaction between methane and chlorine is shown. CH4 + 4Cl 2 → CCl 4 + 4HCl Which type of reaction does methane undergo? A substitution B reduction C condensation D addition

Question

Which functional groups form an amide linkage? A H2N– and –COOH B H2N– and H2N– C –OH and –COOH D –OH and H2N–

Question

The structure of propene is shown. H H H H C C C H H Which diagram represents poly(propene)? A B C D H H H H H H C H H H H H C H H H C C C C C C C C C C H H H n H H n H H n H H n

Question

The equation shows the formation of a polymer called Kevlar. n HOOC COOH + n H 2N NH2 – H2 O O O C C N N H H n Which row describes Kevlar? how the polymer is formed type of polymer A addition polymerisation polyamide B addition polymerisation polyester C condensation polymerisation polyamide D condensation polymerisation polyester 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.).