Physical Sciences Grade 12 P2 KZN Mock 2025 Question Paper

S KWAZULU-NATAL PROVINCE EDUCATION REPUBLIC OF SOUTH AFRICA NATIONAL SENIOR CERTIFICATE PHYSICAL SCIENCES P2 (CHEMISTRY) PREPARATORY EXAMINATION SEPTEMBER 2025 150 TIME : 3Hours This question paper consists of 15 pages and 4 data sheets. Copyright reserved Please turn over

INSTRUCTIONS AND INFORMATION 4. Write your name in the appropriate spaces on the ANSWER BOOK. 2s This question paper consists of NINE questions. Answer ALL the questions in the ANSWER BOOK. Bi Start EACH question on a NEW page in the ANSWER BOOK. 4. Number the answers correctly according to the numbering system used in this question paper. 5; Leave ONE line between two sub-questions, for example between QUESTION 2.1 and 2.2. 6. You may use a non-programmable calculator. G You may use appropriate mathematical instruments. 8. Show ALL formulae and substitutions in ALL calculations. 9. Round off your final numerical answers to a minimum of TWO decimal places. 10. Give brief motivations, discussions et cetera where required. Ti. You are advised to use the attached DATA SHEETS. 12. Write neatly and legibly. Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination QUESTION 1: MULTIPLE-CHOICE QUESTIONS Four options are provided as possible answers to the following questions. Each question has only ONE correct answer. Choose the answer and write only the letter (A-D) next to the question number (1.1-1.10) in the ANSWER BOOK, for example 4.11. 41.1 Which ONE of the following compounds represents an ester? | i ae H-—C—O—C—H H tod ll | O 4H fe) H Cc i D i H—-O—-C—C—H H—C —O—H of f ; ou H (2) 1.2 Which ONE of the following compounds has the LOWEST vapour pressure? A Butanal. B_ Pentane. C Butan - 1 - ol. D_ Propanoic acid. (2) 1.3 Consider the reaction represented by the equation below: CsH1iBr + NaOH — CsH120 + NaBr This reaction is an example of. . . A Hydration. B_ Dehydration. C_ Substitution. D_ Hydrogenation. (2) Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination 1.4 Consider the reaction represented by the balanced equation below: 2S03(g) = 2S02(g) + O2(g) AH = 198 kJ.mol™ Which ONE of the following is TRUE for the reaction? When 2 moles of SO2(g) are formed... A 198 kJ of energy is absorbed. B 198 kJ of energy is released. C 396 kJ of energy is absorbed. D 396 kJ of energy is released. (2) 1.5 Calcium carbonate reacts with excess hydrochloric acid according to the following chemical equation: CaCOa(s) + 2HC£(aq) + CaCfle(aq) + CO2(g) + H2O(£) In an investigation, VARYING MASSES of calcium carbonate are added to EQUAL AMOUNTS of HC and the gas released is collected. The following graph is produced from the results of one experiment: o, Volume of CO2(g) (dms) Which ONE of the following conclusions about the reaction is correct at time, t indicated in the graph? A HCtis used up in the reaction. B CaCOsis in excess. C CaCOs is used up in the reaction. D Both, HC? and CaCOs are in excess. (2) Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination 1.6 Which one of the following statements below regarding a reversible reaction taking place in a closed container is true? A_ When chemical equilibrium is reached the value of K, is zero. B Chemical equilibrium is reached when the forward reaction stops. C Chemical equilibrium is reached when the concentrations of the product and reactants remain constant. D- Chemical equilibrium is reached when the concentration of the products (2) is equal to the concentrations of the reactants. 1.7 Water is added to a 0,01 mol-dm” solution of nitric acid. Which one of the following describes the change in concentration of hydronium ions and pH in this solution as water is added? [H20*] pH Remains the same Remains the same Increases Decreases Increases Increases A B Cc D Decreases Increases (2) 1.8 Bromophenol blue is an acid-base indicator that has a colour change from yellow to blue between pH 3,0 and 4,6. A NaOH solution is titrated with an acetic (ethanoic) acid solution, using bromophenol blue indicator. Which one of the following statements about this titration is true? The end point and the equivalence point occur at the same time. The end point occurs after the equivalence point. The end point occurs before the equivalence point. The indicator will be yellow at the equivalence point of the titration. (2) DOWD Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination 1.9 The emf of a galvanic cell is found to be 1,2 V under standard conditions. The following half-reactions and standard electrode potentials are provided: Half reaction E® value (V) J te ed -1,8 Q+ 2e += Q 0,3 Li +t oe «sa £ -0.,9 M+ 2e = M -0,3 Which of the substances J, K, L and M will act as the anode and cathode respectively? A JandL B JandM C LandM D LandQ (2) 1.10 When copper is extracted from its ores, the impure copper, which contains small amounts of silver and gold, is purified by electrolysis. During this process, a “sludge” forms beneath the anode which is found to contain silver and traces of gold. Why is silver found in this sludge? A _ Silver is a weaker oxidising agent than copper. B __ Silver is an inert metal, so will not dissolve during the electrolysis. C __ Silver reacts with the electrolyte to form an insoluble salt. D Silver is more dense than copper and falls off the cathode. (2) [20] Copyright reserved Please turn over

Physical Sciences/P2 QUESTION 2 (Start on a new page.) The letters A to E in the table below represent five organic compounds. 2.1 2.2 2.3 September 2025 Preparatory Examination H oH | | H#-G-e—8 H HH H oH HH | | | | | | H—-c—-c—~cC—~CG—~C—C—C-—H | | | | | | H H H Br oH H H—C—H | H CH3CH(CHs)CHCH2 | C | CHsCH2COCHs | D | CHsCOO(CH2)2CHs3 Write down the IUPAC name of the compound: 2.1.1 A 2.1.2 B Write down general formula for compound D. Write down the letter that represents the compound that: 2.3.1 Belongs to the same homologous series as ethanal. 2.3.2 Has a carbonyl carbon atom bonded to two carbon atoms. Copyright reserved (3) (2) (1) (1) (1) Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination 2.4 Compound D has functional isomers. 2.4.1 Define the term functional isomers. (2) 2.4.2 Write down the empirical formula of the functional isomer of compound D. (2) 24.3 Write down the IUPAC name of the functional isomer of compound D. (2) [14] QUESTION 3 (Start on a new page.) Organic compounds X, Y and Z are used to investigate one of the factors that influences a physical property of organic compounds. The table below shows the results obtained. Organic Compound | BOILING POINT (°C) WwW 138 x 129 Y 114 Compounds W, X and Y are CHAIN [SOMERS with a molecular formula of CsH120. The FUNCTIONAL GROUP FOR EACH COMPOUND IS POSITIONED on the first carbon atom for the purposes of this investigation. 3.1 Define boiling point. (2) 3.2 Write down the: 3.2.1 Reason why the functional group for each compound is positioned on the first carbon atom for the purposes of this investigation. (1) 3.2.2 Name of the weakest intermolecular force between molecules of W. (1) 3.2.3 Name of the strongest intermolecular force between molecules of Y. (1) 3.4 Which compound W, X or Y will have the highest vapour pressure? Give a reason for the answer. (2) 3.5 Although compounds W and X have the same molecular, they have different boiling points. Fully explain the difference in boiling points. (4) 3.6 Draw the structural formula for compound Y. (3) 3.7 Will the boiling point of 2,2 — dimethylpropane be HIGHER THAN, EQUAL TO or LOWER THAN the boiling point of compound Y? Fully explain the answer. (4) [18] Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination QUESTION 4 (Start on a new page.) In the flow diagram below, 1, 2 and 3 represent organic reactions. A, B, C and D represent organic compounds. Compound B ao tertiary alcohol Compound A CH3sCH2CH2C(CH3)CH2 HBr 2 Compound G 7 >| CompoundD + KBr Compound A produces compounds B and C during reactions 1 and 2 respectively. ONLY, ONE OF THE COMPOUNDS, EITHER B OR C IS A MAJOR PRODUCT. 4.1 Write down a SINGLE term for the type of reaction represented by 1 and 2. (1) 4.2 Define the term tertiary alcohol. (2) 4.3 Write down the name or formula of the: 4.3.1 Inorganic reagent/reactant needed for reaction 1. (1) 4.3.2 Catalyst used in reaction 1. (1) 4.4 Write down the: 4.4.1 Structural formula for compound B. (3) 4.4.2 IUPAC name for compound C. (3) 4.5 Compound D belongs to the same homologous series as compound B. 4.5.1 Write down the name of the functional group of the homologous series to which both compounds B and D belong. (1) 4.5.2 Write down the type of reaction represented by reaction 3. Choose (1) from SUBSTITUTION, ADDITION or ELIMINATION. 4.5.3 Besides heat write down ONE reaction condition for reaction 3 that will ensure the formation of the indicated products. (1) 4.5.4 Balanced equation for reaction 3, using molecular formulae. (3) [17] Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination QUESTION 5 (Start on a new page.) 62,25 g of calcium carbonate chips are added to an EXCESS dilute hydrochloric acid solution in a flask placed on a balance as illustrated below. The balanced equation for the reaction that takes place is: CaCO3(s) + 2HCt(aq) + CaCte(aq) + CO2(g) + H20(t) , Gas bubbles hydrochloric acid Calcium carbonate chips 5.1 It is observed that the initial mass of the flask and its contents decreases as the reaction progresses. Write down the reason why the initial mass decreases. (1) The loss in mass of the flask and its contents is recorded. The results obtained are shown in the graph below. Graph of loss in mass versus time \ Loss in mass (g) T T T T T a th te Time (minutes) Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination The average gradient of the above graph for the time interval 0 to t: minutes is 1,37 g.min*. §.2 Define the term reaction rate. (2) 5.3 Explain the shape of the graph for the time interval t1 to te minutes. (2) 5.4 Apart from concentration and temperature changes, write down TWO other changes that can be made to increase the rate of this reaction. (2) 5.5 Calculate the value of t1 in minutes. (8) 5.6 The experiment is now repeated using hydrochloric acid of a higher concentration. How would a higher concentration of hydrochloric acid affect the following: (Write down only INCREASES, DECREASES or REMAINS THE SAME.) 5.6.1 Loss in mass per unit time. (1) 5.6.2 Total loss in mass. Give a reason for the answer. (2) 5.7 Use the collision theory to explain the answer to question 5.6.1 (3) [21] QUESTION 6 (Start on a new page.) Gas A2Q is introduced into a flask, which is then sealed, and allowed to reach dynamic chemical equilibrium at a certain temperature. The gas AzQ decomposes as shown in the balanced chemical equation below: 2A2Q(g) = 2A2(g) + Q2(g) 6.1 Describe ONE method to FAVOUR ONLY the FORWARD reaction. (1) 6.2 Initially 5 moles of the gas A2Q are introduced into the reaction flask. The flask is then sealed and kept at a constant temperature. When dynamic chemical equilibrium is established, 70.59 % of the gas A2Q has decomposed and the concentration of gas Q2 in the flask is 0,8825 mol.dm*. Calculate the value of the equilibrium constant (Kc) for this reaction at this constant temperature. (9) Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination The graph below shows the changes in the rates of the forward and reverse reactions with time for the reaction above. 2 4 a4 0 6 60 120 180 240 Time (s) 6.3 A change was made to the reaction at 120 s. Refer to the graph and write down a reason for why this change is NOT the addition of a catalyst. (1) 6.4 State Le Chatelier’s Principle. (2) 6.5 The temperature was changed at 180 s. Refer to the graph and Le Chatelier’s Principle to write down how this change in temperature will affect the Kc value. Choose from GREATER THAN, EQUAL TO or LESS THAN the value calculated in question 6.2. (1) 6.6 Refer to the graph and Le Chatelier’s Principle to explain the answer to question 6.5. (3) [17] Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination QUESTION 7 (Start on a new page.) 7.4 The salt sodium ethanoate (CHsCOONa) is produced when ethanoic acid (CHsCOOH) reacts with sodium hydroxide (NaOH). #ahat Write down the formula of the conjugate base of the acid CH3sCOOH. (1) 7.1.2 Will the pH of a solution of sodium ethanoate be GREATER THAN 7, EQUAL TO 7 or LESS THAN 7. (1) 7.1.3 Write a balanced equation to support the answer to question 7.1.2 (3) 7.2 An aqueous solution HC reacts with an aqueous solution of NazCOs according to the following balanced equation: 2HCt(aq) + NazCOs(aq) — 2NaCf£(aq) + CO2(g) + H2O0(t) T2A Define the term strong acid. (2) 50 cm of a solution of dilute hydrochloric acid, HC£(aq) is added to 25 cm? of a 0,075 mol.dm® solution of sodium carbonate, NazCOs(aq) at 25 °C. The HCt is in EXCESS. The concentration of the EXCESS HC in the resulting solution is 0,013 mol.dm*. 1.22 Calculate the pH of the 50 cm? of HC? solution that was initially added to the NazCOs solution. Assume the temperature remains at 25°C; (10) [17] Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination QUESTION 8 (Start on a new page.) A electrochemical cell is set up, under STANDARD CONDITIONS as shown below. A standard hydrogen electrode is connected to metal X in a solution of its ions. wy wa xis} - rin 1 HCe(aq) The following observations were made while the cell was in operation: (I) The pH of the HC{(aq) decreases. (Il) The initial emf of the cell is 0,34 V. 8.1 Which electrode, X or Pt is the anode of the above cell. (1) 8.2 Does the mass of the platinum (Pt) INCREASE, DECREASE or REMAIN the same while the above cell is in operation? (1) 8.3 Write down the: 8.3.1 Half-reaction to support the answer to question 8.1 (2) 8.3.2 Initial temperature at which the above electrochemical cell operates. (1) 8.3.3 Initial concentration of the HC£(aq) solution. (1) 8.4 Refer to the table of standard reduction potential table to write down the formula of the cations in the cathode compartment of the above cell. (1) 8.5 Hence write down the cell notation for this cell. (3) 8.6 The hydrogen half-cell is replaced with another half-cell that undergoes oxidation. The initial emf of the cell under STANDARD CONDITIONS changes to 0,75 V. Fully explain if the platinum electrode is still required. (Choose from YES or NO) Support the answer with a relevant calculation. (6) [16] Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination QUESTION 9 (Start on a new page.) Two different cells, A and B are shown in the diagrams below. Cell A contains a concentrated solution of sodium chloride (NaCt) and cell B contains a concentrated solution of copper(II) chloride (CuCtz). P, Q, R and S are identical carbon electrodes. Chlorine gas is formed at electrode P and S. routes ] _| Power i source I | P Q R s ! | NaCt (aq) --——> +-—-—}-CuCh (aq CellA CellB 9.1 Are the above cells ELECTROLYTIC or GALVANIC? Give a reason for your answer. (2) 9.2 Define an electrolyte. (2) 9.3 Write down the equation for the half reaction taking place at electrode Q. (2) 9.4 Write down the NAME or SYMBOL of the product formed at electrode R. (1) 9.5 What happens to the concentration of the electrolyte in cell B when the cell is in operation? Write down INCREASES, DECREASES or REMAINS THE SAME. Give a reason for the answer. (3) [10] [150] Copyright reserved Please turn over

Physical Sciences/P2 DATA FOR PHYSICAL SCIENCES GRADE 12 PAPER 2 (CHEMISTRY) GEGEWENS VIR FISIESE WETENSKAPPE GRAAD 12 VRAESTEL 2 (CHEMIE) TABLE 1: PHYSICAL CONSTANTS/TABEL 1: FISIESE KONSTANTES September 2025 Preparatory Examination NAME/NAAM SYMBOL/S/MBOOL VALUE/WAARDE Stendearadnak p* 1,013 x 10° Pa Moles panvelliie bi SED Vim 22,4 dm*-mot* Standgardion erate " 273K leaireanensn e 4,6 x 10°C sei a la Na 6,02 x 102° mot TABLE 2: FORMULAE/TABEL 2: FORMULES m N n=— n=— M Na n m Vv c=_— or/of c=— n=— Vv MV Vin CaVa _ Ma - . Civ, My PH = -log[H30*] Kw = [H3O*][OH] = 1 x 10° at/by 298 K 8 8 8 6 8 8 Feat = E cathode — Fi tls /EQ = Ejatoas — Eanode or/of 8 8 8 . eo 8 Eee = Eaten ~ Eoxidation! Eee) = Fauna — Eorsidasie or/of 8 8 8 8 8 8 Eee = Ee scangagant = Eiesicrgagent IES = Eo rsideermidde! ~ Edusoermiddel | Q Q_ where n is the number of electrons/ AL ~@ Waarn die aantal elektrone is Copyright reserved Please turn over

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Physical Sciences/P2 September 2025 Preparatory Examination TABLE 4A: STANDARD REDUCTION POTENTIALS TABEL 4A: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies £9 (V) F2(g)+2e- = 2F- + 2,87 Co*+e- = Co% +1,81 H202+2H*+2e- = 2H20 +1,77 MnO; +8H*+5e- = Mn%+4H2O | +4,54 Ch(g)+2e = 2Ch + 1,36 CrOF +14H*+6e- = 2Cr+7H20 | +1,33 O2(g)+4H*+4e- = 2H20 #1,23 MnO2+ 4H*+2e- = Mn?*+2H2O + 1,23 . Pit +2e- pt + 1,20 Bro(t)+2e- = 2Br + 1,07 NO; +4H*+3e- = NO(g)+2H20 | +0,96 © Hg?*+2e- = Hg(2) + 0,85 2 2 Agt+e = Ag + 0,80 g E NO; +2H*+e- = NO2g)+H20 | +0,80 g g Fe*+e- = Fe +0,77 & 3 2g) + 2H*+2e° =. H2O2 + 0,68 s 5 Ib+2e = 2b + 0,54 3 by Cut+e = Cu + 0,52 3 3 SO2+4H++4e- 2S +2HL0 + 0,45 c s 2H20 + O2+4e- we 40H- +0,40 3 ® Cu +2e- = Cu + 0,34 ® § SO% +4Ht+2e- = SOx(9)+2H20| +0,17 4 £ Cut+e = Cur +0,16 5 o c Sn4*+2e- = Sn? +0,15 Lad 8 S+2H*+2e = HS(g) +014 2 Ls 2H*+2e- = Hig) 0,00 = = Fe*+3e- = Fe — 0,06 a 2 Pb?*+2e- = Pb - 0,13 £ o Sn%*+2e- = Sn -0,14 s = Ni*+2e- = Ni —0,27 3 S Co*+2e- = Co - 0,28 = * Cd*+2e- = Cd - 0,40 £ o Cette = Cr -0,41 8 £ Fe?*+2e- =: Fe - 0,44 2 a cr++3e- Cr 0,74 2 5 Zn**+2e- = Zn -0,76 £ 2H20+2e- = He(g)+20H- | -0,83 Cr++2e- = Cr -0,91 ¥ Mn**+2e- = Mn -1,18 AGt+3e- = AL - 1,66 Mg?*+2e- = Mg — 2,36 Nat+e- = Na -2,71 Ca*%*+2e = Ca — 2,87 Sr*+2e- = Sr — 2,89 Ba**+2e- = Ba — 2,90 Cst+e = Cs - 2,92 Ktte = K —2,93 litte = Li ~3,05 Copyright reserved Please turn over

Physical Sciences/P2 September 2025 Preparatory Examination TABLE 4B: STANDARD REDUCTION POTENTIALS TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E° (Vv) litte = Li = 3,05 Ktte = K = 2,93 Cst+e = Cs -2,92 Ba**+2e- = Ba — 2,90 Sr++2e = Sr — 2,89 Ca%*+2e- = Ca — 2,87 Nat*+e = Na -2,71 Mg**+2e- = Mg — 2,36 AB++3e = AL —1,66 s Mn**+2e- = Mn —1,18 0 Cr++2e- = Cr -0,91 £ 2H20+2e- = Ha(g)+2OH- | -0,83 o Zn**+2e- = Zn -0,76 3 A Cre+3e = Cr 0,74 & 3 Fe +2e = Fe -0,44 g ry Crtt+e = Cr -0,41 a g Cd*+2e 2 Cd -0,40 zg G Co*+2e- = Co —0,28 2 i Ni*+2e = Ni -0,27 3 gz Sn?*+2e° = Sn -0,14 3 5 Pb? +2e = Pb -0,13 £ S Fe*+3e = Fe —0,06 zg = 2Ht+2e 4 Hala) 0,00 5 e S+2H*+2e = HeS(g) +0,14 5 > Sn4++2e = Sn* +0,15 5 = Cu +e = Cu* +0,16 °c a S07 +4H*+2e- = SOx(g)+2H20 | +0,17 > E Cu2*+2e- = Cu + 0,34 = a 2H20+O2+4e- = 40H- +0,40 rs 3 SOQ2+4H*+4e- = S+2H20 + 0,45 > 3 Cutte = Cu +0,52 3 = l+2e° = 2b + 0,54 3 Oo O2(g) + 2H*+ + 2e- = H202 + 0,68 = Fy Fe*+e = Fe* +0,77 > £ NO3 +2Ht+e- = NOz(g)+H20 | +0,80 a v Agt+e- = Ag +0,80 s Hg2*+2e- = Hg(t) + 0,85 £ NO3 +4H*+3e- = NO(g)+2H20 | +0,96 Bro(t)+2e- = 2Br + 1,07 Pet+2e = Pt + 1,20 MnO2+4H*+2e- = Mn%+2H,0 | +1,23 O2(g)+4H*+4e- = 2H20 + 1,23 crO? +14H*+6e = 2Cr*+7H20 | +1,33 Ch(g)+2e- = 2Ct + 1,36 MnOz +8H*+5e- = Mn+ 4H20 +1,51 H2O2+2H*+2e- = 2H20 41,77 Co*%+e- = Co* +1,81 F2o(g)+2e- = 2F + 2,87 Copyright reserved