Chemistry 9701/12 May/June 2024: question paper and mark scheme

Question

Which pair of formulae is correct? A Ag2CO3 and (NH4)3NO3 B K2HCO3 and Zn3(PO4)2 C AgHCO3 and K3PO4 D ZnCO3 and (NH4)2PO4

Question

How many molecules are present in 62 g of solid white phosphorus, P4? A L B 2L C L D L 2 4

Question

The first eight successive ionisation energies for two elements of Period 3 of the Periodic Table are shown in the graphs. ionisation ionisation energy energy 0 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 electron removed electron removed What is the formula of the ionic compound formed from these elements? A MgCl 2 B CaBr2 C Na2S D K2Se

Question

In which pairs are both species free radicals? 1 Cl and O 2 Cl – and O2– 3 Cl and O– 4 Cl + and O2+ A 1, 3 and 4 B 1 and 3 only C 1 only D 2 only

Question

Which shape is correctly predicted by VSEPR theory? number of bonded number of shape electron pairs lone pairs A 2 2 linear B 2 2 tetrahedral C 3 1 pyramidal D 3 1 trigonal planar

Question

In which species does the underlined atom have an incomplete outer shell? A BF3 B CH3– C F2O D H3O+

Question

In this question it should be assumed that nitrogen behaves as an ideal gas under the conditions stated. Which volume is occupied by 1.00 g of nitrogen at 50.0 °C and at a pressure of 120 kPa? A 0.124 dm3 B 0.799 dm3 C 1.60 dm3 D 22.4 dm3

Question

Consider the following four compounds. 1 (CH3)3CH 2 CH3CH2CH2OH 3 CH3CH2CH2SH 4 CH3CH2CH2CH3 What is the order of increasing boiling point of the compounds (lowest first)? A 1→4→2→3 B 1→4→3→2 C 4→1→2→3 D 4→1→3→2

Question

Ethane can react with fluorine to produce 1,2-difluoroethane, C2H4F2. C2H6 + 2F2 → C2H4F2 + 2HF ΔH = –960 kJ mol–1 energy bond / kJ mol–1 C–H 410 C–C 350 F–F 158 H–F 562 What is the bond energy of the C–F bond in 1,2-difluoroethane? A 407 kJ mol–1 B 474 kJ mol–1 C 486 kJ mol–1 D 972 kJ mol–1

Question

Which equation has an enthalpy change equal to the standard enthalpy of formation of sodium oxide? A Na(s) + 1 4 O2(g) → 1 2 Na2O(s) B Na(s) + O2(g) → Na2O(s) C 2Na(s) + 1 2 O2(g) → Na2O(s) D 4Na(s) + O2(g) → 2Na2O(s)

Question

Nitrogen dioxide reacts with water. 2NO2 + H2O → HNO2 + HNO3 Which statement about this reaction is correct? A Both products are formed because oxygen atoms gain electrons. B Nitrogen atoms undergo disproportionation. C The oxidation number of hydrogen is increased. D Water acts as an oxidising agent.

Question

Phosphorus reacts with concentrated sulfuric acid to produce phosphoric acid, sulfur dioxide and water. aH2SO4 + bP → cH3PO4 + dSO2 + eH2O a, b, c, d and e are all whole numbers. The equation can be balanced by using oxidation numbers. What is the value of the sum a + b + c + d + e? A 10 B 14 C 15 D 16

Question

The volume of ammonia produced against time is measured in two experiments. N2(g) + 3H2(g) 2NH3(g) ∆H = –92 kJ mol–1 In experiment 1, 3 mol of H2(g) and 1 mol of N2(g) react together at 45 °C and a pressure of 200 atm. A graph showing the volume of ammonia produced against time is plotted. Experiment 2 is then performed. Experiment 2 differs from experiment 1 in one condition only. experiment 1 experiment 2 volume of NH3 0 0 time How does experiment 2 differ from experiment 1? A An iron catalyst is present in experiment 2. B 2 mol of helium gas is present in the reaction mixture in experiment 2. C A pressure of 250 atm is used in experiment 2. D A temperature of 600 °C is used in experiment 2.

Question

Which reaction has an equilibrium constant, Kp, that has no units? A H2(g) + I2(g) 2HI(g) B 3H2(g) + N2(g) 2NH3(g) C 2NO2(g) N2O4(g) D 2SO2(g) + O2(g) 2SO3(g)

Question

Gas Q decomposes slowly at room temperature. Q(g) → X(g) + Z(g) The Boltzmann distribution curve for gas Q at room temperature is shown. number of particles 0 0 Ea energy Which change occurs when a catalyst is added to gas Q? A The peak of the curve moves to the right on the diagram. B The number of particles with enough energy to decompose increases. C The kinetic energy of the unreacted particles increases. D The value of Ea decreases, moving the vertical dotted line to the right on the diagram.

Question

Which statement is correct? A Aluminium chloride has a giant ionic lattice of Al 3+ and Cl – ions. B Sodium chloride dissolves in water, forming hydrogen chloride and sodium hydroxide. C The strong covalent bonds in silicon chloride prevent it from reacting with water. D When phosphorus(V) chloride is added to water, the resulting solution conducts electricity.

Question

A mixture of calcium carbonate, calcium nitrate, strontium carbonate and strontium nitrate is thermally decomposed. The decomposition reaction of each substance goes to completion. Each substance is anhydrous. How many different products are formed? A 4 B 5 C 7 D 8

Question

W is a solid that reacts with water to produce an alkaline solution. The addition of two drops of dilute H2SO4 to this alkaline solution produces a white precipitate. What could be the identity of solid W? A magnesium hydroxide B magnesium oxide C barium oxide D phosphorus oxide

Question

Chlorine gas is reacted with cold aqueous sodium hydroxide. Which statement is correct for this reaction? A Chlorine is both oxidised and reduced. B Chlorine is neither oxidised nor reduced. C Chlorine is oxidised but not reduced. D Chlorine is reduced but not oxidised.

Question

Sodium is added to water to form solution Y. The pH of solution Y is measured. When powdered substance X is added to solution Y, the pH falls. Which two compounds could each be substance X? A MgCl 2 and Al (OH)3 B MgCl 2 and K2O C NaCl and Al (OH)3 D NaCl and K2O

Question

The table shows statements about some of the properties of halogens and their compounds and explanations for these properties. Which row shows a correct statement about the property and a correct explanation for the statement? statement explanation A iodine is a solid at room temperature the I–I bond strength is high B the decomposition of hydrogen iodide chlorine is more is more endothermic than the reactive than iodine decomposition of hydrogen chloride C when chlorine is bubbled into aqueous chlorine is a stronger potassium iodide, a purple solution is seen oxidising agent than iodine D when concentrated sulfuric acid is added to iodide ions are being oxidised solid potassium iodide, a purple vapour is seen to iodine by the sulfuric acid

Question

Which statement describes a property of an ammonium ion? A An aqueous ammonium ion is a weak Brønsted–Lowry base. B Aqueous ammonium sulfate reacts with dilute hydrochloric acid to make ammonia gas. C An ammonium ion has a pyramidal shape with an H–N–H bond angle of 107°. D The four N–H covalent bonds in an ammonium ion are identical to each other.

Question

Catalytic converters are fitted in the exhaust systems of many cars. Gas X: ● causes acid rain if it is released into the air ● is removed from car exhaust fumes by a catalytic converter. What is gas X? A carbon dioxide B carbon monoxide C hydrocarbon vapour D nitrogen dioxide

Question

In the general formula of which class of compound is the ratio of hydrogen atoms to carbon atoms the highest? A alcohols B aldehydes C carboxylic acids D halogenoalkanes

Question

Which statement is correct? A Adding sodium oxide to water gives a lower pH solution than adding silicon oxide to water. B The oxidation state of sodium in its chloride is higher than the oxidation state of silicon in its chloride. C The atomic radius of sodium is larger than that of silicon. D The melting point of the chloride of sodium is lower than the melting point of the chloride of silicon.

Question

Z is a gaseous hydrocarbon which has a density of 3.50 × 10–3 g cm–3 under room conditions. Z reacts with an excess of hot concentrated acidified KMnO4. Only one type of carboxylic acid is formed in this reaction. What is Z? A but-2-ene B 2,3-dimethylbut-2-ene C hex-2-ene D hex-3-ene

Question

Compound X can be oxidised to compound Y. Compound Y gives a yellow precipitate with alkaline I2(aq). What is compound X? A butan-1-ol B butan-2-ol C methylpropan-1-ol D methylpropan-2-ol

Question

Aqueous NaOH reacts with 1-bromopropane to give propan-1-ol. What should be included in a diagram of the first step in the mechanism? A a curly arrow from a lone pair on the OH– ion to the Cδ+ atom of 1-bromopropane B a curly arrow from the Cδ+ atom of 1-bromopropane to the OH– ion C a curly arrow from the C–Br bond to the C atom D the homolytic fission of the C–Br bond

Question

In which reaction is the organic compound oxidised? A CH3CH2CH2CHO + Tollens’ reagent B CH3CH2CH2CHO + LiAl H4 C CH3CH2CH2OH + concentrated H3PO4 D CH3CO2C2H5 + dilute H2SO4 30 1 mole of each of the following four compounds is reacted separately with: ● an excess of sodium ● an excess of sodium carbonate. Which compound produces the same volume of gas with each of the two reagents? A B C D OH O O O OH OH H HO HO HO HO O

Question

In the question paper above.

Question

Which reaction will distinguish between propan-1-ol and propan-2-ol? A warming with acidified KMnO4 B warming with acidified K2Cr2O7 C dehydration, followed by reaction with Br2(aq) D mild oxidation, followed by reaction with Fehling’s reagent

Question

Compound T has the skeletal formula shown. compound T Which structure is a structural isomer of compound T? A B C D

Question

The diagram shows a simplified structure of coenzyme Q10. coenzyme Q10 O CH3O CH3O H O n Which row describes the structure of coenzyme Q10 correctly? number of π bonds the coenzyme is in one molecule A an aldehyde n+2 B an aldehyde n+4 C a ketone n+2 D a ketone n+4

Question

The molecule of limonene, C10H16, contains a 6-membered ring. This is the only cyclic component in its structure. Which volume of hydrogen, at room conditions, is required to react completely with the C=C double bonds in one mole of limonene? A 12 dm3 B 24 dm3 C 48 dm3 D 72 dm3 35 1-bromopropane reacts with hot ethanolic NaOH. What is the molecular formula of the product in this reaction? A C3H6 B C3H8 C C3H7O D C3H8O

Question

In the question paper above.

Question

A sample of pent-2-en-4-ol, C5H10O, contains all the possible stereoisomers of this compound. How many stereoisomers are there in the sample? A 2 B 3 C 4 D 5

Question

Which pair of reagents reacts to form a product with a chiral carbon atom? A CH3CH=CH2 + HBr B (CH3)2C=O + NaBH4 C CH3CH2CHO + HCN D CH3COOH + CH3CH2OH

Question

The diagrams show the structures of two esters, X and Y, that are formed in ripening apples. ester X ester Y O O O O Which carboxylic acids are formed when these esters are hydrolysed by H2SO4(aq)? ester X ester Y A CH3COOH CH3CH2COOH B CH3COOH CH3CH2CH(CH3)COOH C CH3CH(CH3)CH2COOH CH3CH2COOH D CH3CH(CH3)CH2COOH CH3CH2CH(CH3)COOH

Question

An addition polymer is made from monomer Z. monomer Z O CH2 CH C OCH2CH3 What is the structure of the polymer made from this monomer? O A CH CH C n O B CH CH C O n C CH2 CH C O n OCH2CH3 D CH2 CH n C OCH2CH3 O

Question

Compound X reacts with acidified K2Cr2O7 to form compound Y. The infrared spectrum of compound Y is shown. 100 transmittance 50 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 characteristic infrared absorption range bond functional groups containing the bond (in wavenumbers) / cm–1 C–O hydroxy, ester 1040–1300 C=C aromatic compound, alkene 1500–1680 C=O amide 1640–1690 carbonyl, carboxyl 1670–1740 ester 1710–1750 C≡N nitrile 2200–2250 C–H alkane 2850–2950 N–H amine, amide 3300–3500 O–H carboxyl 2500–3000 hydroxy 3200–3600 What is the identity of compound X? A propan-1-ol B propan-2-ol C propanone D propanoic acid Important values, constants and standards molar gas constant R = 8.31 J K–1 mol–1 Faraday constant F = 9.65 × 104 C mol–1 Avogadro constant L = 6.022 × 1023 mol–1 electronic charge e = –1.60 × 10–19 C molar volume of gas Vm = 22.4 dm3 mol–1 at s.t.p. (101 kPa and 273 K) Vm = 24.0 dm3 mol–1 at room conditions ionic product of water Kw = 1.00 × 10–14 mol2 dm–6 (at 298 K (25 °C)) specific heat capacity of water c = 4.18 kJ kg–1 K–1 (4.18 J g–1 K–1) The Periodic Table of Elements Group 1 2 13 14 15 16 17 18 1 2 H He hydrogen helium Key 1.0 4.0 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 6.9 9.0 relative atomic mass 10.8 12.0 14.0 16.0 19.0 20.2 11 12 13 14 15 16 17 18 Na Mg Al Si P S Cl Ar sodium magnesium aluminium silicon phosphorus sulfur chlorine argon 23.0 24.3 3 4 5 6 7 8 9 10 11 12 27.0 28.1 31.0 32.1 35.5 39.9 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 39.1 40.1 45.0 47.9 50.9 52.0 54.9 55.8 58.9 58.7 63.5 65.4 69.7 72.6 74.9 79.0 79.9 83.8 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 16 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 85.5 87.6 88.9 91.2 92.9 95.9 – 101.1 102.9 106.4 107.9 112.4 114.8 118.7 121.8 127.6 126.9 131.3 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 132.9 137.3 178.5 180.9 183.8 186.2 190.2 192.2 195.1 197.0 200.6 204.4 207.2 209.0 – – – 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 138.9 140.1 140.9 144.4 – 150.4 152.0 157.3 158.9 162.5 164.9 167.3 168.9 173.1 175.0 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 – 232.0 231.0 238.0 – – – – – – – – – – –