Physical Sciences Grade 12 P2 KZN Mock 2023 Paper & Memo

Downloaded from Stanmorephysics.com J KWAZULU-NATAL PROVINCE EDUCATION REPUBLIC OF SOUTH AFRICA NATIONAL SENIOR CERTIFICATE eS SSSR RRR T EERE R REE a " PHYSICAL Sd RY) " “ e . PREPAR Hi a n s i s i . " WIETTTETITTiTiiry eeeeeesnseseee® MARKS: 150 TIME : 3Hours This question paper consists of 14 pages and 4 data sheets. Copyright reserved Please turn over

September 2023 Preparatory Examination Physical Sciences/P2 2 Downloaded from Stanmohphysics.com INSTRUCTIONS AND INFORMATION 1. 10. 11. 12. Write your centre number and examination number in the appropriate spaces on the ANSWER BOOK. This question-paper consists of NINE questions. Answer ALL the questions in the ANSWER;BOOK. Start EACHiquestion on a NEW page in the ANSWER BOOK. Number the answers correctly according to the numbering system used in this question paper. Leave ONE line between two sub-questions, for example between QUESTION 2.1 and QUESTION 2.2. You may use a non-programmable calculator. You may use appropriate mathematical instruments. You are advised to use the attached DATA SHEETS. Show ALL formulae and substitutions in ALL calculations. Round off your final numerical answers to a minimum of TWO decimal places. Give brief motivations, discussions et cetera where required. Write neatly and legibly. Copyright reserved

Physical Sienpes/@tded from Stanmorephysicsreone 2023 Preparatory Examination iC QUESTION 1: MULTIPLE-CHOICE QUESTIONS Various options are provided as possible answers to the following questions. Choose the answer and write only the letter (A-D) next to the question number (1.1-1.10) in the ANSWER BOOK, forexample 1.11 D. 1.1 1.2 1.3 Which ONE of the following homologous series does NOT contain a CARBONYLIGROUP? A Esters B_ Alcohols Cc. Aldehydes D Carboxylic acids (2) Which of the following statements COULD apply to compounds that are structural isomers of one another? (I) They have the same structural formula. (Il) They have the same molecular formula. (Ill) They may belong to the same homologous series. A (I), (Il) and (III) B (I) and (Ill) C (1) and (Il) D (II) and (III) (2) Compound X undergoes a combustion reaction according to the following equation: 2X + 1902 > 12COz + 14H20 What is the IUPAC name of compound X? A Hexane B Hex-2-ene C Propane D Hexanoic acid (2)

Physical Sciences/P2 4 September 2023 Preparatory Examination Downloaded from Stanmorfhysics.com 1.4 The energy changes represented by X, Y and Z on the potential energy graph below takes place during a catalysed, reversible chemical reaction. Potential e Course of reaction Which ONE of the following represents the heat of the reaction for the FORWARD reaction? X-Y Zex X-Z (2) oO 0D > 1.5 Which ONE of the following statements correctly describes the rate of reaction for the following reaction? Mg(s) + 2HC£(aq) — MgCé2(aq) + H2(g) The time it takes to use up the reactants. The decrease in the concentration of magnesium per unit time. The time it takes for one of the reactants to be completely used up. oo |QaQ DUD F The increase In the concentration of MgCf2(aq) per unit tim (2) Copyright reserved

Physical Sciences/P2 5 September 2023 Preparatory Examination NSC Downloaded from Stanmorephysics.com 1.6 Consider the reaction represented by the following balanced chemical equation: Ha(g) + lag) = 2HI(g) The system is initially at equilibrium. The pressufe is increased by decreasing the volume of the container at constant/femperature. How will the amount of HI(g) and the concentration of HI(g) change? AMOUNT OF HI (g) CONCENTRATION OF HI (g) A Remains the same Remains the same B Decreases Decreases c Remains the same Increases D Remains the same Decreases 1.7 Consider the reaction represented by the balanced equation below: HeSOx(aq) + H20(t) > HsO*(aq) + HSOs(aq) Which ONE of the following is a conjugate acid-base pair? A HsO*(aq) and H2O() B HsO%{aq) and HSO« (aq) G —H2SOa(aq) and H20(@) DB —- H2SQa(aq) and HsO0*(aq) 18 Which ONE of the foltow!ng gives the approximate pH of an aqueous solution of sodium carbonate and the relevant hydrolysis equation? pH HYDROLYSIS EQUATION Less than 7 COs? ¥ HGOs- Mote Less than 7 Nat: + H20 = NaOH /#>H* Greater than 7 CO3? + H20 = HCO3- + OH OJOQ;]oa] > Greater than 7 Nat + HeO = NeOH + Hf mere on (2) (2)

1.9 Dasvenibefceablyanineelbisahn®eadn stiedard eanditions. The following half reactions and standard electrode potentials are provided. HALF REACTION STANDARD ELECTRODE POTENTIAL(E’) IN VOLTS(V) eas - Wt + re Ww 1,8 2 = x” + [Be = x +03 ¥* = -0,9 Z+ + 2e 2Z -0,3 Which ONE of the following combinations is correct for the above galvanic cell? ANODE CATHODE O/O;];na|> (2) 1.10 Consider the following reactions for a metal P: (i) P reacts with a solution of silver nitrate resulting in a deposit of metallic silver. (ii) P does not react with a solution of zinc sulphate. Which ONE of the following correctly lists the metals, P; Ag and Zn in order of DECREASING strengths of reducing agents? A P; Ag; Zn B Zn; P; Ag Cc Ag; P; Zn py D Ag; Zn; P (2) [20] Copyright reserved Please turn over

Physical Sciences/P2 ri September 2023 Preparatory Examination Downloaded from StanmoréPhysics.com QUESTION 2 (Start on a new page.) The letters A to F in the table below represent organic compounds. a i A} H — i — 1 _ i Cc —H CH3 H CHs as B) H — ‘om i -—- C= c— ’ —H CH3 H H Cc | CHsCH2CH2CH2CH2COOH D | CsHsO2 E | Pentan —2 - one F | 2,2 —dimethylpropane Use the information in the table to answer the questions that follow. Write down the general formula of the homologous series to which compound B 2.1. Write down the letter/s that represent/s: 2.1.1. TWO compounds with a pH less than 7 2.1.2 ACHAIN ISOMER of CHs(CH2)3CHs 2.1.3. A substance with a fruity smell 2.2 Write down the IUPAC name of compound A. 2.3 Define the term homologous series. 24 belongs 2.5 A straight chain organic acid X, ethanol and a catalyst are heated to produce the organic compound G. The equation below represents the reaction that takes place: X + C2Hs0H —+— G + H20 The molecular mass of compound G is 116 g.mol"' and its empirical formula is C3HeO. 2.5.1. Write down the name of the reaction that produces compound G. (2) (1) (1) (2) (2) (1) (1)

2.6 2.7 2.5.2 Write down the NAME or FORMULA of the catalyst that can be used in Dow RASA FFA Stanmorephysics.com 2.5.3. Write down the STRUCTURAL FORMULA of the organic compound X. (3) Define the term functional isomer. (2) Write down the STRUCTURAL FORMULA of the FUNCTIONAL isomer of compound E. (2) [18] QUESTION 3 (Start.oma new page.) Organic compounds A, B, C and D of comparable molecular mass are used to investigate the relationship between homologous series and vapour pressure at a temperature of 20°C. The results obtained are shown in the table below. 3.1 3.2 3.3 3.4 ORGANIC COMPOUND VAPOUR PRESSURE (kPa) at 20 °C A 1,6 B 2 Cc 24,6 D 204 Define vapour pressure. (2) Give a reason why the temperature is specified. (1) For this experiment write down the: 3.3.1 Dependent variable (1) 3.3.2 Controlled variable (1) Arrange the compounds A, B, C and D in order of INCREASING boiling point. (2) The compounds A, B, C and D IN RANDOM ORDER represent propan—1—ol, ethanoic acid, butane and 2-propanone. 3.5 3.6 3.7 Write down the vapour pressure of ethanoic acid at 20 °C. (1) Fully explain the answer to Question 3.5 by referring to intermolecular forces and vapour pressures. (3) Which compound represents 2-propanone? Explain how you arrived at the answer (4) [15]

Physical Sciences/P2 9 September 2023 Preparatory Examination Downloaded from Stanmorepiftysics.com QUESTION 4 (Start on a new page.) In the flow diagram below, I, Il, Ill, IV and V are organic reactions. X, Y and Z represent organic compounds. COMPOUND Z F Vv 2-bromobutane -—————»| 9 MAJORPRODUCT -=——— > COMPOUND X HCL rY IV il COMPOUND Y 4.1 Reaction | is an elimination reaction. 4.1.1 Name the type of elimination reaction taking place. (1) 4.1.2 Write down the structural formula for the MAJOR PRODUCT formed. (2) 4.1.3. Write down the balanced equation for the reaction using MOLECULAR FORMULAE. (3) 4.2 Reaction Il is an addition reaction. Write down the IUPAC name of COMPOUND X. (2) 4.3 In reaction II], COMPOUND X, is heated with dilute sodium hydroxide. 4.3.1. Name the type of reaction taking place. (1) 4.3.2 | Write down the IUPAC name of COMPOUND Y. (2) 44 In reaction IV COMPOUND Y, is heated under reflux with concentrated sulphuric rv Name the type of reaction taking place. (1) 4.4.2 Write down the NAME or FORMULA of the INORGANIC product formed. (1) 4.5 Compound Z is a saturated hydrocarbon. 4.5.1 Name the type of addition reaction represented by reactior-V. (1) 4.5.2 Write down the NAME or FORMULA of the catalyst used in reaction V. (1) , [15] Copyright reserved Please turn over

Physical Sciences/P2 10 September 2023 Preparatory Examination NSC Downloaded from Stanmorephysics.com QUESTION 5 (Start on a new page) Manganese dioxide (MnOz) catalyses the decomposition of a solution of hydrogen peroxide, H2O2(aq): 2 H2O02(aq) > 2H20(f) + O2(g) Manganese dioxide jof-mass 0,1 g was added to a flask containing 200 cm® of a solution of hydrogenjperoxide of concentration 0,2 mol.dm. The oxygen gas produced was collected at standard temperature and pressure and the volume measured every minute using @ gas syringe. The following graph was obtained: Graph of Volume of oxygen gas formed vs Time 140 = 120 === = & a m 100 o a c 80 oe oa Z 2 Z 3 60 a Z © 40 Z E A Oo 20 x > f- A. ¢ > 1 2 3 4 5 6 7 8 9 Time in minutes The reaction stops before all the hydrogen peroxide decomposes. 5.1. How long did it take for the reaction to stop? 5.2 How does the volume of oxygen gas collected compare for EVERY MINUTE as the reaction progresses? Choose from INCREASES, DECREASES or REMAINS THE SAME. 5.3. What mass of manganese dioxide is present in the flask after 8 minutes? 5.4. Using the collision theory, fully explain the shape of the graph from the time the reaction starts to the time the reaction stops, 5.5 Using the information provided and the graph, calculate the concentration of the hydrogen peroxide REMAINING when the reaction has stopped. (1) (1) (1) (4) (9) [16]

PwasgWHodded from Stanmorephysics. QUESTION 6 (Start on a new page) 6.1 6.2 Consider the reaction represented by the balanced equation below: NO2(g) + SO2g) = SOsx(g) + NO(g) Initially 2 s of NOz(g) and'2 moles of SO2(g) were mixed in a sealed 2 dm? containe en equilibrium is reached at 700 °C there are 60 g of SOsa(g) present container. 6.1.1. Define the term chemical equilibrium. 6.1.2 Calculate the value of the equilibrium constant, Ke, for this reaction. as that decomposes into colourless p gas, Cia(g), at a temperature Nitrosyl chloride gas, nitrogen monoxide, above 100 °C. + Ch(g) green Some NOCt gas is seale contal en equilibrium is reached, a mixture of NOCfz, NO and Cfz with a yellow-green colour is present in the container. 6.2.1 State Le Chatelier’s Principle. The pressure in the container is changed without changing the temperature, resulting in the colour of the mixture changing to green. 6.2.2 Was the pressure INCREASED or DECREASED? Use Le Chatelier’s Principle to explain the answer. 6.2.3. How does the change in pressure affect the amount of NO(g) at equilibrium? Choose from INCREASES, DECREASES or NO EFFECT. 6.2.4 State ONE other change that can be made to the above system at equilibrium to bring about the same change to the amount of NO(g) identified in QUESTION 6.2.3 September 2023 Preparatory Examination com (2) (7) (2) (3) (1) (1) [16]

Physical Sciences/P2 12 September 2023 Preparatory Examination NSC . Downloaded from Stanmorephysics.com QUESTION 7 (Start on a new page.) 7.1. The acid HF ionizes according to the following equation: HF +H20 = Hs0* (aq) + F*(aq) When a 0,10 mol-dm® solution of HF Is prepared, it is found that the concentration of thte-F° ions is 0,018 mol-dm’ at 25 °C. 7.1.1 Define a/strong acid. (2) 7.1.2. Is HF asStrohg acid? Choose from YES or NO. Give a reason for the answer. (2) 7.1.3 Calculate the [OH’] in this solution. (3) 7.2 Sodium hydroxide (NaOH) pellets of mass X g are added to sufficient distilled water to prepare a solution of volume 25 cm? in a flask. 12 cmé of sulphuric acid, H2SO«, of concentration 0,10 mol-dm* is added to the flask containing the sodium hydroxide. The total volume of the mixture formed is 37 cm? and its pH is 12,56. H2SO. (aq) + 2NaOH (aq) — NazSO4 (aq) + 2 H20 (£) 7.2.1 Explain the term dilute acid. (2) 7.2.2 How does the concentration of the hydronium ions compare to the concentration of the hydroxide ions in the mixture? Choose from LARGER THAN, SMALLER THAN or EQUAL TO. (1) 7.2.3 Calculate the value of X. (8) [18] Copyright reserved Please turn over

Physical Sciences/P2 MA September 2023 Preparatory Examination NS ques RON's ees eth Frew pafgmorephysics.com An electrochemical cell is set up under standard conditions using a hydrogen half-cell and a nickel half-cell as shown in the simplified diagram below. Ni Platinum H*(aq) t— Ni? (aq) 8.1 State the standard conditions, besides a temperature of 25 °C, under which this cell operates. (2) 8.2 Calculate the initial reading on the voltmeter. (4) 8.3 For this electrochemical cell, write down: 8.3.1. The energy conversion that takes place (1) 8.3.2 One function of component Q (1) 8.3.3 Direction in which the anions in component Q will move. Choose from TOWARDS THE NICKEL HALF CELL or TOWARDS THE HYDROGEN HALF CELL (1) 8.3.4 Half reaction that takes place at the anode (2) 8.4 How will the pH of the solution in the hydrogen half-cell be affected after a while? Choose from INCREASES, DECREASES, or REMAINS THE SAME. Explain the answer. (3) 8.5 The platinum electrode is replaced with a larger platinum electrode. How will this affect the initial emf of the cell? (Choose from INCREASES, DECREASES or NO EFFECT) (1) [15] Copyright reserved Please turn over

Physical Sciences/P2 14 September 2023 Preparatory Examination Downloaded from Stanmorephysics.com QUESTION 9 (Start on a new page.) 9.1 9.2 9.3 9.4 9.5 9.6 The simplified diagram below represents an electrolytic cell used to purify copper. battery |= CuSOa(aq) Define the term electrolysis. Which electrode, R or T, consists of pure copper? Give a reason for the answer. Write down the half reaction that takes place at electrode R. How will the concentration of the electrolyte be affected while the cell is functioning? Choose from INCREASES, DECREASES, or REMAINS THE SAME. Give a reason for the answer Zinc is one of the impurities found in the impure copper. Will the presence of zinc ions influence the quality of the refined copper? Choose from YES or NO. Refer to relative strengths of oxidising agents to explain the answer. A constant current is registered on the ammeter and 1,72 g of the copper is deposited on the cathode in 30 minutes. Calculate the reading on the ammeter. TOTAL (2) (2) (2) (2) (3) (6) [17] 150

Downloaded fron StanpacepnyatarG FRADE 12 GEGEWENS VIR FISIESE WETENSKAPPE GRAAD 12 VRAESTEL 2 (CHEMIE) TABLE 1: PHYSICAL CONSTANTS/TABEL 1: FISIESE KONSTANTES NAME/NAAM SYMBOL/S/MBOOL VALUE/WAARDE TABLE 2: FORMULAE/TABEL 2: FORMULES m N n=— n=— M Na n m _V any] orlof arr n= V, LAP Pate) pH a -log[H30*] Coy My Kw = [HaO*][OH'] = 1 x 10-4 at/by 298 K (25°C) or/of =a = Ee athode = Ee node =m = E Ketode > Ee node een = E reduction — Eoaidation / Eee = Erecuisie SS Ectskasle 8 6 8 ducingagent / Eee — E okstdeermidde! ad Ereduscermdel or/of Ee = Fe siatgapart ~ Es, q = IAt - Q n= rs or/of electrons Q Se Where n is the number of Copyright reserved Please turn over

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Physical Sciences/P2 Downloaded Fegan <StoowuesenlvaliaetPorceace TABEL 4A: STANDAARD-REDUKSIEPOTENSIALE Copyright reserved Increasing oxidising ability/Toenemende oksiderende vermoé KZN September 2023 Preparatory Examination Half-reactions/Halfreaksies E% (vy) F2(g)+2e- = 2F- + 2,87 Co*+e- = Co* + 1,81 H202+ 2H*+2e- = 2H20 +1,77 MnO; +8H*+5e- = Mn? +4H20 +1,51 Cex(g)+2e- = 2Ce + 1,36 C07 +14H* +60 = 2Cr*+7H.0 | +1,33 On(g)+4H* +4e- = 2H20 + 1,23 MnOz+ 4H* + 2e7 == =Mn?* + 2H20 +1,23 Pt} +2e- = Pt +1,20 Br.(@)+2e- = 2Br +1,07 NO; +4H*+3e- = NO(g)+2H20 | +0,96 Hg*+2e- = Hg(e) + 0,85 Agtte = Ag + 0,80 NO3 +2H*+e = NO2(g)+H20 + 0,80 Fe%+e- = Fett +0,77 Ox(g) + 2H* + 2e-° = = H202 + 0,68 In+2e° = 2b + 0,54 Cut+e> = Cu + 0,52 S$O2+4H'+4e> = S$+2H:0 + 0,45 2H20+0Oz2+4e- = 40H + 0,40 Cu*+2e- = Cu + 0,34 S07 +4H'+2e- = SOx(g)+2H20| +0,17 Cu*+e = Cut + 0,16 Sn“+2e = Sn* +015 S+2H*+2e = H2S(g) +0,14 2H*+2e = Ha(g) 0,00 Fe*+3e = Fe - 0,06 Pb*+2e = Pb -0,13 Sn*+2e = Sn -0,14 Ni#+2e- = Ni -0,27 Co**+2e- = Co - 0,28 Cd*+2e- = Cd -0,40 Cr++e- = Cr* - 0,41 Fe++2e- = Fe -0,44 Cr++3e- = Cr -0,74 Zn*+2e- = Zn - 0,76 2H20+2e- = H2(g)+20H- | -0,83 Crt++2e- = Cr = 0,91 Mn?* + 2e- = Mn -1,18 At*+3e- = AC = 1,86 Mg**+2e- = Mg - 2,36 Na*+e- = Na -2,71 Ca**+2e- = Ca — 2,87 Sr’+2e- = Sr — 2,89; Ba*+2e- = Ba — 2,90- Cs*+e = Cs + 2,92 Kite = K — 2,93 Lit+e = Li - 3,05 Increasing reducing ability/Toenemende reduserende vermoé Please turn over

Physical Sciences/P2 4 September 2023 Preparatory Examination Downloaded from Stanmorephysics.com TABLE 4B: STANDARD REDUCTION POTENTIALS TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies Ee Luvte = LI = 3,05 Ki +e = K - 2,93 Cst+e = Cs - 2,92 Ba’*+2e- = Ba — 2,90 S420 = Sr - 2,89 Ca*+2e = Ca — 2,87 ij Nat*+e- = Na -2,71 9 Mg*+2e = Mg — 2,36 § AQ +3e- = AL — 1,66 3S Mn?*+2e- = Mn -1,18 4 z Cr*+2e = Cr - 0,94 E = 2H20 + 2e- = H2(g)+2OH- | -0,83 g s Zn*+2e° = Zn - 0,76 o 3 Cr*+3e = Cr 0,74 ES g Fe*+2e- = Fe - 0,44 £ : Cr*+e- = Cre - 0,41 g Ss Cd*+2e = Cd -0,40 3 5 Co%+2e- = Co - 0,28 2 § Ni? +2e- = Ni - 0,27 3 5 Sn%+2e- = Sn -0,14 5 2 Pe +26 = Pb - 0,13 5 3S Fe*+3e = Fe - 0,06 5 = 2H*+2e- = Hag) 0,00 2 2 S+2H*+2e- = H2S(g) + 0,14 > 2 Sn*+2e = Sn? + 0,15 e ‘a Cu* +e" = Cur +0,16 4 3 S07 +4H*+2e- = SOxg)+2H20| +0,17 > ° Cu*+2e = Cu + 0,34 5 > 2H20+02+4e" = 40H" +0,40 3 ri SOQ2+4H* +40" = S+2H20 + 0,45 £ 2 Cut+e = Cu + 0,52 = gS In+2e° = 2 + 0,54 7] =¥ Ox(g) +2H* +207 = H:02 +0,68 2 Fe*+e = Fo +0,77 2 NO; +2H*+e- = NOxg)+H20 | +0,80 zy Ag’ +e = Ag + 0,80 Hg +2e- = Hg(e) + 0,85 NO; +4H*+3e = NO(g)+2H20 | +0,96 Br2(@)+ 2e- = 2Br +41,07 Pt? +2e° = Pt + 1,20 MnO2+ 4H’ + 2e =) =~ Mn® + 2H20 + 1,23 O2(g) +4H* + 4e" = = 2H20 +1,23 Cr03 +14H*+6e = 2Cr*+7H20 | +4,33 Céx(g)+2e = 208 + 1,36 MnO, +8H*+5e- = Mn*+4H:0 | +1,54 H202+ 2H* +267 = 2H20 +1,77 Copyright reserved Co*+e- = Co* + 1,81 F2x(g)+2e- = 2F- + 2,87

Downloaded from Stanmorephysics.com KWAZULU-NATAL PROVINCE EDUCATION REPUBLIC OF SOUTH AFRICA GRADE 12 NATIONAL SENIOR CERTIFICATE MARKS: 150 This marking guideline document consists of 13 es. Copyright reserved Please turn over

PhysicdDeugtebeiazled from Stanmorephysics . COB*ptember 2023 Preparatory Examination NS QUESTION 1 1.1 Byv 1.2 Dvv 1.3 AVY 1.4 Avy 1.5 Dvv 1.6 Cvv 1.7 AVY 1.8 Cvv 1.9 Byv 1.10 Byy QUESTION 2 2.1 2.1.1 Cv Dv (accept E) 2.1.2 FY 2.1.3 DorEv 2.2 2—methylpent — 1 — enevv Marking criteria: © correct stem and substituents: methyl and penteneY” e IUPAC name completely correct including numbering, sequence and hyphen ¥ 2.3 A series of organic compounds that can be described by the same general formula vv OR A series of organic compounds in which one member differs from the next by a -CH2 group.v ” Marking criteria: If any one of the underlined key words/phrases in the correct contextis omitted, deduct 1 mark. 2.4 CrHan-2¥ Copyright reserved (2) [20] (2)

PhysicdDawsoteleiazied from Stanmorephysics. compember 2023 Preparatory Examination NS 2.5.1 Esterification/ester formation” (1) 2.5.2 Sulphuric acid/H2SOav (1) 2.5.3 a ‘ i i ve ~N H —l0r— C —C\— C — 0 — H) vv (3) H H H —— _— Marking criteria: e Functional group correctly drawn” e 4carbons v e Whole structure correctly drawnv 2.6 Compounds with_same molecular formulay but different functional groups. v (2) 27 eo H H H H/ O \ vv | | | on } H—C—C—C— C\—~C —H / | | | _— / H H H HO ~~ Marking criteria: e Functional group correctly drawn” M e 2 Whole structure correct ¥ x (2) ACCEPT structures for: 2-methylbutanal, 3-methylbutanal and 2,2-dimethylpropanal. [18] Copyright reserved Please turn over

PhysicdDeasetehoaaed from Stanmorephysics. compember 2023 Preparatory Examination NS QUESTION 3 3.1 3.2 3.3.1 3.3.2 3.4 3.5 3.6 3.7 The pressure exerted by a vapour at equilibrium with its liquid in a closed system jy“ Marking Criteria: If any one of the underlined key words/phrases in the correct context (vapour pressure) is omitted, deduct 1 mark. (2) Vapour pressure is temperature dependent” (1) Vapour pressure “ (1) Molecular massv OR Temperature. Accept: straight chainY (1) D; C; B; A vv (2 OR ZERO) (2) 1,6 (kPa)v (1) For ethanoic acid: Strongest intermolecular forces between the molecules (Hydrogen bonds).” Most energy required to overcome the intermolecular forces. v Lowest vapour pressure (3) Marking criteria: e Correct answer (C) e¢ Compare strengths of IMFs of A and B, and relate to vapour pressureY e Compare strengths of IMFs of D, and relate to vapour pressure” e Compare strengths of IMFs of C with A, B and D.v Pa al —_—s ar d/ethanoic acid/A and alcohol/propan-1-ol/B have orces resulting in lowest vapour pressures. V termolecular forces resulting in the highest vapour has intermolecular forces stronger-than Butane/D, but weaker than carboxylic acid/ethanoic acid/A and alcohol/propan-1-ol/B. ” lanai (4) L [15] Copyright reserved Please turn over

PhysicdDawsoteleiazied from Stanmorephysics. compember 2023 Preparatory Examination NS QUESTION 4 4.1.1 Dehydrohalogenation / Dehydrobromination” (1) 4.1.2 H HH H bay 4 | H — Tn c= CH T —H Marking criteria: ¢ Functional group correctly drawn’ A e Whole structure correct “ % (2) 4.1.3. CaHoBr +NaQH — CaHs + NaBr + H20 (any strong base) LHSv RHSv_ BALY NOTE: If structural formulae used, max 2/5 (3) 4.2 2 - chlorobutanev v Marking criteria: * correct stem and substituents: chloro and butanev e IUPAC name completely correct including numbering, sequence and hyphen v (2) 4.3.1 Hydrolysis” or substitution (1) 4.3.2 butan — 2 - ol’v” OR 2-butanol Marking criteria: © correct stem and substituents: butanol” e IUPAC name completely correct including numbering, sequence and hyphen v (2) 4.4.1 Elimination Yor dehydration (1) 4.4.2 Water/H20v (1) 4.5.1 Hydrogenationv (1) 4.5.2 — Platinum/Pt OR Nickel/Ni OR Palladium/Pd (1) [15] Copyright reserved Please turn over

PhysicdDawsoteleiazied from Stanmorephysics. compember 2023 Preparatory Examination NS QUESTION 5 5.1 7 (minutes) ¥ 5.2 Decreases-~ 5.3 01g” 5.4 Gradient of;the graph decreases as the reaction progresses. v Rate of the reaction decreases. Vv Concentration of H2Oz decreases as the reaction progresses / Amount of reacting molecules decreases in the same volume. ¥ Number of effective collisions per unit time decreases. “ 5.5 Marking criteria: Copyright reserved e Formula: n = ~ ¥ to calculate n(O2)produced m 0116 answer (5,179 x 10° if substitution is not shown)” e Ratio: n(H2O2) used equals 2n(Oz) produced ~ © Correct substitution ( ) in the above formula / Award mark for e Use n=cV to calculate n(H20z) initial e n(H2O2) when reaction stops = n(H2O2)initial - n(H2Oz2)used/reacted vv e Formula: C = av to calculate C required e Correct substitution into the formula: c = — v as Vv e Final answer = 0,15 mol-dm3 v Please turn over (1) (1) (1)

PhysicdDawsoteleiazied from Stanmorephysics. compember 2023 Preparatory Examination NS 5.5 Copyright reserved OPTION 1: n(Oz)produced = = + v m _ 9116 22,4 Any one ¥ = 5,179 x 10° mol n(H2Oz2) used = 2n(O2) producedY = 2(5,179 x 10°) = 0,010358 mol n(H2O2) initial =cV = (0,2)(0,2) v = 0,04 mol n(H2O2) when reaction stops = n(H2Oz)initial - n(H2Oz)used/reacted 0,04 - 0,010358v v 0,029642 mol Cc = as v V _ 0,029642 v 0,2 = 0,15 mol-dm3’ Y_ Range: 0,1482 to 0,15 OPTION 2: n(Oz)produced = a v m _ 0116 ~ 22,4 = 5,179 x 10° mol 2H202 2H20 O2 R 2 2 1 I 0,04” 0 C -0,010358v (Ratio) +5,179 x 10°V_ > END 0,029642vV 5 Ava 10% Cc = a v Vv _ 0,029642 | 0,2 = 0,15 mol-dm? vv Range: 0,1482 to 0,15 Please turn over (9) [16]

PhysicdDawsoteleiazied from Stanmorephysics. compember 2023 Preparatory Examination NS QUESTION 6 6.1.1. When the rate of forward reaction equals the rate of reverse reaction. vv OR when the amounts of reactants and products remain constant. Notes IF: Forwardhreaction equals reverse reaction. % (2) 6.1.2 | Marking criteria: e n(SOs) equilibrium = 0,75“ e Using the correct mol ratiov e Calculating the quantity(mol) at equilibrium of all three substances “ e Divide number of moles at equilibrium by 2 dm°v e Ke expression’ e Correct substitution of equilibrium concentrations into Ke expression ¥ e Kce=0,36Y NO2 SOz2 SOs NO Ratio 1 1 1 1 Initial quantity (mol) 2 2 0 0 Change (mol) 0,75 | 0,75 0,75 | 0,75 Using ratio v Quantity at equilibrium (mol) 4,25 1.25 | O75 v O75 >) v Equilibrium concentration (mol-dm3) | 9,625 0,625 | 9,375 | 0,375 | Divide by 2 v x, SOL] INOL , * (NO, ][SO,] = (0:375)(0.375) No K, expression, correct substitution: Max % Round brackets used for Ke expression: Max 6/7 (0,625) (0,625) = 0,36 v Wrong K, expression: Max A (7) 6.2.1 When the equilibrium in a closed system is disturbed, the system will re-instate a new equilibrium by favouring the reaction that will oppose the disturbance. vv Marking criteria: If any one of the underlined key deduct 1 mark. Phrases must be in correct context. words/phrases in the correct contextis omitted, Copyright reserved Please turn over

PhysicdDawsoteleiazied from Stanmorephysics. compember 2023 Preparatory Examination NS 6.2.2 Decreasedv Green implies forward reaction/ reaction that produces a larger number of molecules is favoured. Vv According to LCP a decrease in pressure favours the reaction that produces a larger nunaber of gas molecules / gas molesv 6.2.3 Increasés =“ 6.2.4 Increase concentration of reactantsY (by adding more) OR decrease concentration of products (by removing some) QUESTION 7 7.1.1 lonises completely in water v'to form a high concentration of H3O* ions.” ACCEPT: lonises completely in water v Y (for 2023 Prep Exams). 7.1.2 Nov Does not ionise completely”/ ionises partially/0,018 mol.dm’ is less than 0,10 mol:dm? 7.1.3 Kw=[HsO*][OH] = 1 x 10-4” (0,018)[OH"] = 1 x 10°14” [OH] = 5.56 x 10° mol-dm?v 7.2.1. Contains a small amount (number of moles) of acid in proportion to the volume of water / in a given volume of water. vv 7.2.2 | SMALLER THANY 7.2.3 Marking criteria: Copyright reserved e Substitute in the formula pH = - log[HsO*]/[H3O*][OH’] = 1 x 10°14/ log[OHV/pH + pOH =14 to calculate c(OH")excess vv tute sasthe formula n = cV to calculate n(OH’) in excess “ oles of OH" reacted with H2SOzs. (ratio as well as excess moles to moles reacted of NaOH (total number of f NaOH) v ¥ e Substitution of molar mass (40) to calculate mass of NaOHY e Final answer 0,144 g. v RANGE: 0,144 g TO 0,149 g NOTE: If the calculation is done using a table, mark within the-table using the criteria above. Please turn over (3) (1) [16] (2) (2) (3) (2) (1)

PhysicdDawsoteleiazied from Stanmorephysics..comtotember 2023 Preparatory Examination NS = - log[Hs0*] OR 14-pH =-log[OH}] 14 — 12,56 v= -logl[OH]” [OH] =0,0363 mol-dm* pH 4#2j56 = - logi[H30*] v fHsO*] = 2,75 x 10°*3 mol-dms H30*][OH] = 1 x 10°14 2,75 x 10°3[OH] = 1 x 10°4¥ [OH] = 0,0363 mol-dmv? n(OH*)excess = cV n(OH) = ce) V OR | (0,0363)(0,037) = 1,3431 x 10° mols n(OH)reacted with H2SO4 = = 2n(H2SOa) = cw n(OH)in 25cm? = eo) Y OR (2)(0,1)(0,012) = 2,4 x 10% mols OR n(H2SO4) = exV = 0,1 x 0,012 = 0,0012 n(NaOH) = 2 x 0,0012 = 0,0024 moles Initial n(NaOH) = 0,0024 + 0,0013 = 0,0037 moles n(total)M (2,4 x 10° + 1.3431 x 10°) vv (40) v 0,149 (g)v m(NaOH) OR n(total)M (0,0024 + 0,0013) v (40) v 0,144 (g)” m(NaOh) (8) Copyright reserved Please turn over

PhysicdDawsoteleiazied from Stanmorephysics..corsotember 2023 Preparatory Examination NS [18] QUESTION 8 8.1 Pressure of.101,3 kPa/ 1 atmv Concentration of electrolytes: 1 mol-dm?” (2) 8.2 =a = Eaaelon — adation v Notes h fi laf h e Accept any other correct formula from the = 0,00 (-0,27) v data sheet. =0,27V v e Any other formula using unconventional abbreviations, ¢.g. E°cer = E°oa- E°ra followed by correct substitutions Max: 3/4, (4) 8.3.1 From chemical to electricalv (1) 8.3.2 Maintain electrical neutrality (of the electrolytes)” Complete the circuit (any ONE) (1) 8.3.3. Towards the nickel half cellv’ (1) 8.3.4 Ni >N?*+2evv (Ignore phases) Notes ° Ni#* +2e—Ni(44) Ni =Ni#?*+2e (%) Ni#+2e=Ni (0%) Ni Ni +2e (9%) e Ignore if charge on electron omitted. If a charge of anion is omitted eg. Ni — Ni+2e Max: (%) (2) 8.4. IncreasesY H* ions are reduced to Ha” Concentration of H* ions decreasesv (3) 8.5 No effectY (1) [15] Copyright reserved Please turn over

PhysicdDawsoteleiazied from Stanmorephysics..corsotember 2023 Preparatory Examination NS QUESTION 9 9.1 9.2 9.3 9.4 9.5 e The chemical process in which electrical energy is converted to chemical energyny Y (2 or 0) OR e The Aisejof electrical energy to produce a chemical change OR e Theprocess during which an electric current passes through a solution/molten ionic compound. (2) T v Reduction takes place (at the cathode) / It is the negative electrode / R is the electrode that is impure Cu.v ACCEPT: So that the Cu forms on pure Cu. (2) Cu(s) — Cu?*(aq) + 2evY Ignore phases Notes © Cu< Cut + 2e (%) Cu?* + 2e- = Cu (%) Cu*+2e<—Cu (34) Cu = Cu*+2e (14) e Ignore if charge on electron omitted. e Ifacharge of an ion is omitted eg. Cu+2e<« Cu Max: (%) (2) REMAINS THE SAMEY The rate at which Cu is oxidised to Cu2* at the anode is equal to the rate at (2) which the Cu2* is reduced at the cathode v Nov Zn?* is a weaker oxidising agent than Cu2*v and will not be reduced. V (3) Copyright reserved Please turn over

PhysicdDaseteteagied from Stanmorephysics.comtotember 2023 Preparatory Examination NS 9.6 Marking criteria: e Substitute in the for Ulate number of moles of Cu. Y * Ratio of number of mols of 6 tolmurt moles of Cu: 2: 1¥ e Substifate in the formula ; late number of electrons” ¢ Substituté in Q = rgev ae I ¢ Substitute in Q = aflans v Fin qe wer 2,89 A n= M n _W2, 63,5 1,72 = 22+ yv n(e) (G35) = 0,054 mol N(e) =nNa = 0,054 x 6,02 x 10% v = 3,2508 x 10% Q = Nde =(3,2508 x 1072)(1,.6 x 107%) v = 5201,28C Q = IAt 5201,28 = 1(1800) I = 2,89 Av (6) [17] TOTAL: 150 Copyright reserved