Chemistry 9701/12 May/June 2023: question paper and mark scheme

Question

When chlorine gas is analysed in a mass spectrometer Cl ions are detected. Which row is correct? number of electronic 35 + 35 + neutrons in Cl configuration of Cl 2 2 6 2 4 A 17 1s 2s 2p 3s 3p 2 2 6 2 6 B 17 1s 2s 2p 3s 3p 2 2 6 2 4 C 18 1s 2s 2p 3s 3p 2 2 6 2 6 D 18 1s 2s 2p 3s 3p

Question

Which species is a free radical? – 2– A He B Be C O D Zn

Question

Which statement is correct? A The first ionisation energy of chlorine is more than the first ionisation energy of argon. B The second ionisation energy of calcium is more than the second ionisation energy of magnesium. C The second ionisation energy of sulfur is equal to the first ionisation energy of phosphorus. D The eighth ionisation energy of chlorine is more than the first ionisation energy of neon.

Question

If 1 mole of hexane combusts in an excess of oxygen, how many moles of products are formed? A 11 B 12 C 13 D 14

Question

Separate samples, each of mass 1.0 g, of the compounds listed are treated with an excess of dilute acid. Which compound releases the largest amount of CO2? A 1.0 g CaCO3 B 1.0 g Li2CO3 C 1.0 g MgCO3 D 1.0 g Na2CO3

Question

Which statement about the Cl –N=O molecule is correct? A EachmoleculecontainsoneSandtwoPbonds. B It is a non-polar molecule. C It is a linear molecule. 2 D The nitrogen atom is sp hybridised . ‹8&/(6 0-

Question

Which row is correct? total number of pairs of electrons in molecule shape the valence shell of the central atom A CO2 linear two B BF3 trigonal planar three C NH3 regular tetrahedral four D PF5 octahedral six –3 3 5

Question

Thevolumeofavesselis1.20s 10 m .Itcontainspureargonatapressureof1.00s 10 Pa, andatatemperatureof25.0°C.Undertheseconditionsitcanbeassumedthatargonbehavesas anidealgas. Which mass of argon does it contain? A 0.0485 g B 1.93 g C 10.4 g D 23.0 g 3 –3 –3

Question

A student mixed 25.0 cm of 4.00 mol dm hydrochloric acid with an equal volume of 4.00 mol dm sodium hydroxide. The initial temperature of both solutions was 15.0 °C. The maximum temperature –1 –1 recorded was 30.0 °C. The heat capacity of the final solution can be assumed to be 4.18 J K g –3 and the density of this solution can be assumed to be 1.00 g cm . Using these results, what is the enthalpy change of neutralisation of hydrochloric acid? –1 A –62.7 kJ mol –1 B –31.4 kJ mol –1 C –15.7 kJ mol –1 D –3.14 kJ mol ‹8&/(6 0- >7XUQRYHU

Question

Nitrogen monoxide is rapidly oxidised to nitrogen dioxide. 2NO(g) + O2(g) → 2NO2(g) Nitrogen dioxide can then dimerise to form dinitrogen tetroxide. 2NO2(g) N2O4(g) ΔH o = –58 kJ mol–1 ΔH of NO = +91 kJ mol–1 and ΔH of NO2 = +34 kJ mol–1 What is the value of the standard enthalpy change for the reaction shown? 2NO(g) + O2(g) → N2O4(g) –1 –1 –1 –1 A +56 kJ mol B –1 kJ mol C –115 kJ mol D –172 kJ mol –

Question

LiAl H4 contains Al H4 ions in which aluminium has an oxidation state of +3. LiAl H4 reacts with water, as shown. LiAl H4 + 4H2O → 4H2 + LiOH + Al (OH)3 In this reaction, each of the four water molecules produces one hydroxide ion. It does this by losing + one H ion, which reacts with the LiAl H4. Which changes in oxidation number occur in this reaction? A Al increases by 1 and H decreases by 1. B H decreases by 2 and also increases by 1. C H increases by 1 and also decreases by 1. D O decreases by 1 and H increases by 1.

Question

Thevanadiumsalt,VOSO4,issolubleinwaterandreactsreadilywithpowderedmanganesein dilutesulfuricacid. Theequationforthereactionisshown. Mn(s) + 2VOSO4(aq) + 2H2SO4(aq) → V2(SO4)3(aq) + MnSO4(aq) + 2H2O(l) Whichstatementaboutthisreactioniscorrect? A Hydrogen is oxidised in the reaction. B Manganese is the reducing agent in this reaction. C Sulfuric acid is the oxidising agent in this reaction. D The oxidation state of the vanadium changes from +5 to +3. ‹8&/(6 0-

Question

Inwhichequilibriumwillanincreaseinpressureatconstanttemperatureincreasetheyieldofthe productsontheright-handsideoftheequation? A CaCO3(s) CaO(s) + CO2(g) B 4HCl (g) + O2(g) 2H2O(g) + 2Cl 2(g) C 2HI(g) H2(g) + I2(g) D 3Fe(s) + 4H2O(g) Fe3O4(s) + 4H2(g)

Question

Hydrogeniodideisaddedtoanevacuatedreactionvessel.Thevesselissealedandwarmed.A decompositionreactionoccurs.Hydrogenandiodineareformed.Somehydrogeniodideremains. 5 Whenequilibriumisestablished,thetotalpressureis1.20s10 Pa.Thepartialpressureofhydrogen 3 is4.00s10 Pa. Hydrogeniodide,hydrogenandiodineareallgaseousundertheconditionsused. WhatisthevalueofKp fortheequilibriumatthistemperature,assumingthedecompositionisthe forwardreaction? –3 –3 –3 –3 A 1.19s10 B 1.28s10 C 1.38s10 D 1.43s10

Question

The equations for two reactions are shown. reaction X 2NOBr → 2NO + Br2 reaction Y 2NOCl → 2NO + Cl 2 The two reactions have similar reaction mechanisms. The initial rate of reaction X is greater than that of reaction Y when measured under identical conditions of temperature, pressure and reactant concentration. Which statements explain this difference? 1 TheactivationenergyforreactionXislessthanthatofreactionY. 2 TheBr−BrbondisweakerthantheCl −Clbond. 3 A higher frequency of collisions between molecules of NOBr occur than between moleculesofNOCl . A 1 and 2 B 2 and 3 C 1 only D 3 only ‹8&/(6 0- >7XUQRYHU

Question

ThediagramshowstheBoltzmanndistributionofenergiesinagas.Thegascantakepartina reactionwithanactivationenergy,Ea.Thegasismaintainedataconstanttemperature. P proportion of molecules with a given energy 0 0 Ea molecular energy Which statement is correct? A If a catalyst is added, peak P will be lower and Ea will move to the left. B If a catalyst is added, peak P will be lower and Ea will move to the right. C If a catalyst is added, peak P will be the same and Ea will move to the left. D If a catalyst is added, peak P will be the same and Ea will move to the right.

Question

L, M and N are three different elements from Period 3 of the Periodic Table. L is the element whose atoms have three unpaired electrons in its 3p sub-shell. M is the element with the highest electrical conductivity in the period. N is the element with the highest melting point in the period. Which statement about element L is correct? A L has a higher atomic number than M and a lower atomic number than N. B L has a lower atomic number than M and a higher atomic number than N. C L has a lower atomic number than both M and N. D L has a higher atomic number than both M and N. ‹8&/(6 0-

Question

In reactions 1 and 2, X represents an element in Period 3. In each reaction, X is forming a product where X is in its highest oxidation state. reaction 1 chlorine + element X → XyCl z reaction 2 oxygen + element X → XpOq Which ratios show a steady increase from sodium to phosphorus? A neither z : y nor q : p B z : y only C q : p only D both z : y and q : p

Question

Sodium, magnesium, aluminium, silicon and phosphorus are all elements in Period 3 of the Periodic Table. Three statements about the oxides and chlorides of these elements are given. 1 The ionically bonded oxides all react with dilute hydrochloric acid. 2 All metal chlorides produce neutral solutions when added to water. 3 The two most electronegative elements both form covalently bonded chlorides. Which statements are correct? A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

Question

The table compares calcium with barium and calcium carbonate with barium carbonate. Which row is correct? reactivity of the thermal stability of element with water the metal carbonate A barium is more reactive barium carbonate is more stable B barium is more reactive calcium carbonate is more stable C calcium is more reactive barium carbonate is more stable D calcium is more reactive calcium carbonate is more stable ‹8&/(6 0- >7XUQRYHU

Question

SolutionsPandQeachcontainadifferentGroup2ionatthesameconcentration.Onecontains 2+ 2+ 3 Mg andtheothercontainsBa .Testsarecarriedoutonseparate5cm samplesofPandQ. 3 –3 test1:add1cm of0.1moldm Na2SO4(aq) 3 –3 test2:add1cm of0.1moldm NaOH(aq) Whataretheresultsofthesetests? results in test 1 results in test 2 2+ 2+ A more precipitate with Ba more precipitate with Ba 2+ 2+ B more precipitate with Ba more precipitate with Mg 2+ 2+ C more precipitate with Mg more precipitate with Ba 2+ 2+ D more precipitate with Mg more precipitate with Mg

Question

J dissolves in water to give an aqueous solution K. K gives a dense white precipitate when aqueous silver nitrate is added. When heated with aqueous potassium hydroxide, K gives off a gas that turns moist universal indicator paper blue. What is J? A ammonium chloride B ammonium sulfate C sodium chloride D sodium hydroxide

Question

Ammonium sulfate, (NH4)2SO4, and ammonium nitrate, NH4NO3, are used as fertilisers. These salts have different percentages by mass of nitrogen. They have the same effect as each other on the pH of wet neutral soil. Which row is correct? higher percentage effect on pH of soil of nitrogen by mass A ammonium nitrate decrease B ammonium nitrate increase C ammonium sulfate decrease D ammonium sulfate increase ‹8&/(6 0-

Question

Theequationshowsareactionthatoccursbetweencarbonmonoxideandnitrogenmonoxideina catalyticconverter. 2CO(g)+2NO(g)→2CO2(g)+N2(g) Whichstatementiscorrect? A The catalyst used is finely divided iron. B The reaction prevents greenhouse gas emissions into the atmosphere. C The reaction reduces the possibility of the formation of photochemical smog. D The reaction results in increased ozone depletion.

Question

Which compound has the molecular formula C6H10O? A B C D O O O OH

Question

The general formula for a non-cyclic alcohol is CnH2n+1OH. How many different structural isomers are there for n = 3 and n = 4? n=3 n=4 A 2 2 B 2 4 C 3 4 D 3 8

Question

CompoundX,C5H10O3,hasonechiralcarbonatompermolecule.CompoundXproducesbubbles withNabutnotwithNa2CO3. WhichformulacouldrepresentcompoundX? A (CH3)2C(OH)CO2CH3 B HOCH2CH(CH3)CO2CH3 C CH3CH2C(CH3)(OH)CO2H D CH3CH(OH)CH(CH3)CO2H ‹8&/(6 0- >7XUQRYHU

Question

Ethane reacts with an excess of chlorine in the presence of ultraviolet light to form a mixture of products. How many of these products contain two carbon atoms and one or more chlorine atoms? A 6 B 7 C 8 D 9

Question

When bromoethane reacts with hot ethanolic sodium hydroxide a colourless gas is formed. This gas decolourises aqueous bromine. What is the colourless gas? A 1,2-dibromoethane B ethanol C ethene D hydrogen bromide

Question

Alkynes are hydrocarbons that contain one triple C≡C bond. Like alkenes, alkynes take part in addition reactions. A saturated compound can be formed. For example, ethyne, H–C≡C–H, reacts with an excess of hydrogen to form ethane. Propyne, C3H4, undergoes an addition reaction with an excess of hydrogen bromide in two stages. Markovnikov’s rule applies to the addition of HBr at each stage. What is the main product obtained when propyne reacts with an excess of hydrogen bromide? A CH2BrCH2CH2Br B CH3CH2CHBr2 C CH3CHBrCH2Br D CH3CBr2CH3

Question

Bromine reacts with alkenes by an electrophilic addition mechanism in which a cation is formed as an intermediate. Which mixture will produce the most stable intermediate cation? A 3,3-dimethylpent-1-ene + bromine B ethene + bromine C methylpropene + bromine D propene + bromine ‹8&/(6 0-

Question

Halogenoalkanes react with hot ethanolic potassium cyanide. The reaction mechanism is either SN1 or SN2. Which statement is correct? A All secondary halogenoalkanes react by the SN2 mechanism only. B Both the halogenoalkane and the cyanide ion are involved in the initial step of the SN1 mechanism. C Chloroethane reacts with cyanide ions by the SN1 mechanism only. D The SN2 mechanism involves a short-lived negatively charged transition state.

Question

X, Y and Z are three isomeric alcohols. X CH3CH2CH2CH2CH2OH Y CH3CH2CH(OH)CH2CH3 Z (CH3)2C(OH)CH2CH3 Separatesamplesofeachalcoholarewarmedwithamildoxidisingagentandtheresultsnoted. Oneofthesealcohols,whendehydrated,willgiveapairofcis-transisomerswithmolecularformula C5H10. Whichrowiscorrect? reacts with mild gives cis/trans oxidising reagents isomers A X, Y and Z Y only B X, Y and Z Z only C X and Y only Y only D X and Y only Z only

Question

Compound G gives a pale yellow precipitate with alkaline I2(aq). What could be compound G? A pentan-1-ol B pentan-2-ol C pentan-3-ol D 2-methylpentan-2-ol ‹8&/(6 0- >7XUQRYHU

Question

The mechanism for the reaction between ethanal and hydrogen cyanide starts with the step shown. H O H C C H H – CN What is the correct structure of the intermediate ion formed, and what is the next step in this mechanism? A B C D H + O H CN H – O H CN H + O H CN H – O H CN H C C H H C C H H C C H H C C H H C H C H C H C N N N N

Question

Which compound reacts with 2,4-dinitrophenylhydrazine reagent but does not react with Tollens’ reagent? A CH3COCO2H B CH3CH(OH)CHO C CH3COCHO D CH3CH(OH)CH3

Question

Compound X has stereoisomers and forms a precipitate when warmed with Fehling’s reagent. What could be the structure of compound X? A B C D O O O O ‹8&/(6 0-

Question

Which reaction will form propanoic acid? A acidic hydrolysis of propyl ethanoate B alkaline hydrolysis of ethyl propanoate C acidic hydrolysis of propanenitrile D acidic hydrolysis of ethanenitrile

Question

Lactide is an intermediate in the manufacture of a synthetic fibre. lactide O O O O Which compound, on heating with an acid catalyst, can produce lactide? A hydroxyethanoic acid B 2-hydroxybutanoic acid C 2-hydroxypropanoic acid D 3-hydroxypropanoic acid

Question

The diagram shows the relative abundance of different isotopes of lead in a sample of lead ore. The abundance of 208 is half that of 206. The abundances of 208 and 209 are equal. 100 75 % abundance 50 25 0 206 207 208 209 Ar What is the relative atomic mass of the lead in the sample? A 207.00 B 207.25 C 207.50 D 207.67 ‹8&/(6 0- ‹8&/(6 0- ,PSRUWDQWYDOXHVFRQVWDQWVDQGVWDQGDUGV PRODUJDVFRQVWDQW R -.±PRO± )DUDGD\FRQVWDQW F u&PRO± $YRJDGURFRQVWDQW L uPRO± HOHFWURQLFFKDUJH e ±u±& PRODUYROXPHRIJDV VP GPPRO±DWVWS N3DDQG. VP GPPRO±DWURRPFRQGLWLRQV LRQLFSURGXFWRIZDWHU KZ u±PROGP± DW. q& VSHFLILFKHDWFDSDFLW\RIZDWHU c N-NJ±.± -J±.±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‹8&/(6 0- ‹8&/(6 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 0- 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 – – – – – – – – – – –