Physical Sciences Grade 12 P2 National Mock 2021 QP

basic education Department: Basic Education REPUBLIC OF SOUTH AFRICA SENIOR CERTIFICATE/ NATIONAL SENIOR CERTIFICATE | GRADE 12 pe SSIS SS © Sie Se Ses § SS Sa 5 55a Ses Ea eee = Sis = =.= i= say " PHYSICAL SCIENCES: CHEMISTRY (P2) Hi iy Li} a PREPARATORY 2021 a Roig oleate tbininiataintarstate etatetetetatetat= stetere eaters a eteletei= sieie sreTetalete® MARKS: 150 TIME: 3 hours This question paper consists of 16 pages and 4 data sheets. x*PHS CE2* Copyright reserves MINION AMIGA please tum over —

Physical Sciences/P2 2. SC/NSC 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 TEN questions. Answer ALL the questions in the ANSWER BOOK. Start EACH question 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 subquestions, e.g. between QUESTION 2.1 and QUESTION 2.2. You may use a non-programmable calculator. You may use appropriate mathematical instruments. 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, etc. where required. You are advised to use the attached DATA SHEETS. Write neatly and legibly. Copyright reserved ANA | Fees rm oven EASTERN CAPE DBE/November 2020(2)

Physical Sciences/P2 3. SC/NSC QUESTION 1: MULTIPLE-CHOICE QUESTIONS DBE/November 2020(2) Four options are provided as possible answers to the following questions. Choose the answer and write only the letter (A-D) next to the question numbers (1.1 to 1.10) in the ANSWER BOOK, e.g. 1.11 E. 4.4 Which ONE of the following is an ALKANE? A CeHs Bo CeHio C CeHi2 D CeHi4 (2) 1.2 Esters are formed by a reaction between two organic compounds, X and Y, each with a different functional group. The functional groups of these compounds are: Compound X Compound Y A Hydroxyl group Carboxyl group B Hydroxyl group Carbonyl group Cc Hydroxide ion Carboxyl group D Hydroxide ion Carbonyl group (2) 1.3 When butane is subjected to high temperatures and pressures, the following reaction takes place: Butane — methane + Y Which ONE of the following represents Y? A CHCCH3 B CHzCHCH3 C CHsCH2CH3 D = CHsCHCHCH3 (2) Certo MN 1 0 001000 Please turn over

Physical Sciences/P2 4. DBE/November 2020(2) SC/NSC 1.4 A hydrochloric acid solution, HCf(aq), of concentration 1 mol-dm® is added to EXCESS POWDERED magnesium at 25 °C. Curve I below represents the volume of hydrogen gas produced during the reaction. Curve II was obtained at different conditions using the SAME VOLUME of hydrochloric acid solution. f Il id Volume of hydrogen gas produced sn ~ Time Which ONE of the following represents the conditions used to obtain curve II? STATE OF DIVISION | CONCENTRATION | TEMPERATURE OF Mg (mol-dm*) (°C) A | Ribbon 0,5 25 B | Ribbon 2 25 C | Powder 4 20 D | Powder 1 30 (2) 1.5 In which ONE of the following reactions at equilibrium will the YIELD of the product increase when the VOLUME of the container is increased at constant temperature? A N20,(g) = 2NO2(g) B Ha(g) + la(g) = 2HI(g) C Nog) + 3H2(g) = 2NHs(g) D —280,(g) + O2(g) = 2802(9) (2) Please turn over Copyright reserved EASTERN CAPE

Physical Sciences/P2 DBE/November 2020(2) 5. SC/NSC 1.6 Which ONE of the following statements is TRUE for an EXOTHERMIC reaction? A More energy is absorbed than released. B- More energy is released than absorbed. C Heat of reaction (AH) is positive. D__ Energy of the products is greater than the energy of the reactants. (2) 1.7 Consider the equation below. HsPO,(aq) + H2O(t) = H3O*(aq) + HPO; (aq) Which ONE of the following is a conjugate acid-base pair? A H30*(aq) and H2O(2) B —_-H3PO,4(aq) and H20(8) C — HsPOs(aq) and H20*(aq) D —_H30*(aq) and H2PO; (aq) (2) 1.8 Consider the balanced equation for the reaction below: 2Cr*(aq) + Sn**(aq) > 2Cr°*(aq) + Sn?*(aq) The OXIDISING AGENT is: A Cr**(aq) B Cr*(aq) Cc Sn**(aq) D Sn**(aq) (2) Copyright reserved CANA | Fieese rm EASTERN CAPE

1.9 1.10 An electrochemical cell is set up at standard conditions. The cell notation for the cell is given below. Mg(s) | Mg**(aq) || Pb**(aq) | Pb(s) The cell is now connected in a circuit. Which ONE of the graphs below BEST represents the concentrations of the electrolytes after a long time? The electrolytic cell illustrated below is used to electroplate a nickel rod with copper. A 4 i= i oO = 5 ,|___Pb*"(aa) 24 g Mg™*(aq) c g Cc fo} oO > Time (s) Cc £ 3 Mg*"(aq) ° — § i 41 3 2+, 5 Pb**(a oO > Time (s) B 5 Pb**(aq) 3 —E & 21 £ c 8 Mg?*(aq) fo} o > Time (s) Mg*"(aq) = Pb**(aq) Concentration (mol-dm’) Time (s) Which ONE of the following is the correct representation of a suitable electrolyte and the nickel rod that should be used in the above cell to obtain the expected results? | ELECTROLYTE NICKEL ROD A | _NiSOdag) __ X. Bo CuSO4(aq) x | ic | NiSO«4(aq) _ : Y D | CuSOs«(aq) Y (2) (2)

Physical Sciences/P2 7. DBE/November 2020(2) SC/NSC QUESTION 2 (Start on a new page.) The letters A to E in the table below represent five organic compounds. H Br CHs CH2CH3 a B | oat 4 i ba CH2CH3 H H H OH c nd id te D | CH3(CH2)2CH(OH)CH2CH3 HAH OA | E | CHsCH2CH2CH2CH2CH2CHCH2 2.1 Write down the LETTER that represents EACH of the following: 2.1.1 A ketone (1) 2.1.2 A hydrocarbon (1) 2.1.3 An alkene (1) 2.2 Write down the: 2.2.1 IUPAC name of compound A (3) 2.2.2 STRUCTURAL FORMULA of compound D (2) 2.2.3 IUPAC name of the STRAIGHT CHAIN FUNCTIONAL ISOMER of compound C (2) 2.3 Compound B is a straight chain compound that undergoes the following exothermic reaction: 2C,Hy + 2502(g) > 16CO2(g) + 18H20(g) 2.3.1 Besides being exothermic, what type of reaction is represented above? (1) 2.3.2 Determine the MOLECULAR FORMULA of compound B. (2) The reaction above takes place in a closed container at a constant temperature higher than 100 °C and at constant pressure. 2.3.3 Calculate the TOTAL VOLUME of gas formed in the container when 50 cm® of C,Hy reacts completely with oxygen. (3) [16] comttecres AINA NAGI)

Physical Sciences/P2 QUESTION 3 (Start on a new page.) Compounds A, B and C are used to investigate a factor which influences the boiling points of organic compounds. The results of the investigation are given in the table SCINSC DBE/November 2020(2) below. COMPOUND BOILING POINT (°C) A_ | Butan-1-ol 117 B | Butan-2-ol : 100 c 2-methylpropan-2-ol 82 : 3.1 ls this a fair investigation? Choose from YES or NO. 3.2 Give a reason for the answer to QUESTION 3.1. 3.3 Fully explain the difference in the boiling points of compounds B and C. 3.4 Define the term positional isomer. 3.5 From compounds A, B and C, choose the letter(s) that represent(s) EACH of the following: 3.5.1 3.5.2 3.6 The graph below represents the relationship between vapour pressure and Positional isomers A tertiary alcohol Give a reason for the answer. temperature for compound A (butan-1-ol). 3.6.1 3.6.2 Copyright reserved Vapour pressure (kPa) Temperature (°C) Write down the value of X. Redraw the graph above in the ANSWER BOOK. On the same set of axes, sketch the curve that will be obtained for compound C. Clearly label the curves A and C. Indicate the relevant boiling point for compound C on the graph. EASTERN CAPE Please turn over (1) (3) (2) (1) (2) (1) (2) [13]

Physical Sciences/P2 9. DBE/November 2020(2) SC/NSC QUESTION 4 (Start on a new page.) 4.1 The flow diagram below shows various organic reactions using propane as starting reactant. R, T and U represent different organic compounds. Compound T is a CARBOXYLIC ACID and compound U is a FUNCTIONAL ISOMER of pentanoic acid. Reaction 1 Reaction 2 Propane | Br, > R Dilute NaQH Propan-1-ol T || Reaction 3 y U Write down the NAME of the type of reaction represented by: 4.1.1 Reaction 1 4.1.2 Reaction 2 Consider reaction 1 and reaction 2. 4.1.3 Write down the IUPAC name of compound R. Reaction 3 takes place in the presence of a catalyst and heat. Write down the: 4.1.4 NAME or FORMULA of the catalyst 4.1.5 IUPAC name of compound T 4.1.6 STRUCTURAL FORMULA of compound U sepamanceseree TANITA EAA Please turn over (1) (1) (2) (1) (2) (2)

Physical Sciences/P2 10. DBE/November 2020(2) 4.2 SC/NSC A laboratory technician wants to prepare but-2-ene using but-1-ene as starting reagent, as shown below. i H— C=C 6 EH —————> _ But-2-ene H H H H The following chemicals are available in the laboratory: [concentrated H2SO4__| H20 | concentrated NaOH _| Select the chemicals required to design this preparation from the list above. For EACH step of the preparation, write down the balanced equation, using STRUCTURAL FORMULAE for all organic compounds. Indicate the chemicals needed in each step. (6) [15] QUESTION 5 (Start on a new page.) 5.1 5.2 5.3 Study the Maxwell-Boltzmann distribution curve for a certain reaction below. P P and Q are the labels of the axes. What quantity is represented by: 5.1.1 P (1) 5.1.2 Q (1) Line R represents the minimum eneray required for the reaction to take place. 5.2.1 Write down the term for the underlined phrase. (1) 5.2.2 How will the shaded area on the graph be affected when a catalyst is added? Choose from INCREASE, DECREASE or REMAINS THE SAME. (1) Use the collision theory to explain how a catalyst influences the rate of reaction. (4) Copys esenes HUNAN Amor

Physical Sciences/P2 11. DBE/November 2020(2) SC/NSC 5.4 The reaction between POWDERED calcium carbonate, CaCO3(s), and EXCESS hydrochloric acid, HCf&aq), is used to investigate reaction rate at 25 °C. The balanced equation for the reaction is: CaCO,(s) + 2HCt(aq) + CaCt,(aq) + H20() + CO2(g) Several experiments are conducted using the same mass of IMPURE calcium carbonate and different initial concentrations of dilute hydrochloric acid. The graph below represents the results obtained. Assume that the impurities do not react. 4 60Rt r Eas seees +H 2 i a oS r t ES (S) 1 t t t w oO " (cm*-min") NO o ne Geena = oO r i" Average rate of production of CO. ine Li = 0 0,005 0,01 0,015 0,02 0,025 0,03 0,035 Initial concentration of HC£ (mol-dm*) For this investigation, write down a: 5.4.1 Controlled variable 5.4.2 Conclusion The CaCo,(s) in 6g of the impure sample reacts completely with 0,03 mol-dm™~ HC£(aq) in 26 minutes. 5.4.3 Use the information in the graph to calculate the percentage purity of the calcium carbonate. Assume that the molar gas volume at 25 °C is 24 000 cm. cere EAA AAA EASTERN CAPE (1) (2) (6) [17]

Physical Sciences/P2 12. DBE/November 2020(2) SC/NSC QUESTION 6 (Start on a new page.) Steam, H20(g), reacts with hot carbon, C(s), at 1 000 °C according to the following balanced equation: 2H,0(g) + C(s) = 2Ha(g) + CO2(g) Initially, 36 g of steam and a certain amount of carbon were placed in a 2 dm® sealed container and allowed to react. At equilibrium it was found that the amount of carbon changed by 0,225 mol. 6.1 Define the term dynamic equilibrium. (2) 6.2 Calculate the equilibrium constant, Ke, for the reaction at 1 000 °C. (8) 6.3 The graph shows how the rates of the forward and reverse reactions change with time. Forward reaction --- Reverse reaction Rate to ty te ts Time 6.3.1 Give a reason why the rate of the forward reaction decreases between tp and ti. (1) 6.3.2 What change was made to the equilibrium mixture at ts? (1) At time te, the temperature of the system is increased. 6.3.3 Is the forward reaction EXOTHERMIC or ENDOTHERMIC? (1) 6.3.4 Refer to Le Chatelier’s principle to explain the answer to QUESTION 6.3.3. (2) [15] comotoes NNN =o

Physical Sciences/P2 13. DBE/November 2020(2) SC/NSC QUESTION 7 (Start on a new page.) Two beakers, A and B, contain strong bases. Beaker A: 500 cm* of barium hydroxide, Ba(OH)2(aq) of unknown concentration X Beaker B: 400 cm? of potassium hydroxide, KOH(aq) of concentration 0,1° mol-dm? 7.1 Define a base according to the Arrhenius theory. (2) 7.2 Calculate the number of moles of hydroxide ions (OH ) in beaker B. (2) 7.3 The contents of beakers A and B are added together in beaker C. The solution in beaker C has a pH of 13. Assume that the volumes are additive and that the temperature of the solutions is 25 °C. / —»* c A B 3 0,1. mol-dm* Ba(OH)(aq) | 500 cm pH = 13 400 cm? | KOH(aq) 7.3.1 Calculate the concentration, X, of the Ba(OH)2 in beaker A. (8) The solution in beaker C is titrated with ethanoic acid. It was found that 15 cm? of the solution neutralises 30 cm’ of the acid. The balanced equation for the reaction is: CH3COOH(aq) + OH (aq) — CH,COO (aq) + H2O(f) 7.3.2 Is ethanoic acid, CH3COOH(aq), a WEAK acid or a STRONG acid? Give a reason for the answer. (2) 7.3.3 Calculate the concentration of the ethanoic acid. (4) [18] Copyright reserved CANA TA AN] FHs ese rm EASTERN CAPE

Physical Sciences/P2 14. DBE/November 2020(2) SC/NSC QUESTION 8 (Start on a new page.) A galvanic cell at standard conditions is represented by the cell notation below. X and Y are unknown electrodes. X | Zn**(aq) || Fe**(aq) , Fe**(aq) | Y 8.1 Write down the NAME or FORMULA of: 8.1.1 Electrode X (1) 8.1.2 Electrode Y (1) 8.1.3 The oxidising agent (1) 8.2 Write down: 8.2.1 ONE function of electrode Y (1) 8.2.2 The half-reaction that takes place at electrode Y (2) 8.2.3 The net (overall) equation for the cell reaction that takes place in this cell (3) 8.3 Calculate the initial emf of this cell. (4) 8.4 How will the initial emf of the cell be affected when the concentration of the iron(IIl) ions is changed to 0,6 mol-dm*? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) [14] Coovmontreserved TANITA AU CUMUTAT MY Pease ten oven EASTERN CAPE

Physical Sciences/P2 15. DBE/November 2020(2) SCINSC QUESTION 9 (Start on a new page.) The simplified diagram below represents an electrochemical cell used for the purification of copper. The impure copper contains small amounts of silver (Ag) and zinc (Zn) as the only impurities. Electrolyte DC source +——Impure copper 9.1 Define the term electrolysis. 9.2 Write down the NAME or FORMULA of TWO positive ions present in the electrolyte. : 9.3 Write down the half-reaction that takes place at the cathode. 9.4 Refer to the Table of Standard Reduction Potentials and explain why the purified copper will NOT contain any zinc. 9.5 Calculate the maximum mass of Cu formed if 0,6 moles of electrons are transferred. Copyright reserved EASTERN CAPE Please turn over (2) (2) (2) (3) (3) [12]

Physical Sciences/P2 16. DBE/November 2020(2) SC/NSC QUESTION 10 (Start on a new page.) Consider the Table of Standard Reduction Potentials below. Half-reactions E® (v) Cr++2e = Or - 0,91 2H2O +2e = Helg)+20H- | -0,83 Zn*+2e = Zn -0,76 Cr+3e = Cr -0,74 Fe*+2e = Fe - 0,44 Cette = Crt -0,41 Sn*+2e = Sn +0,15 Cute = Cut + 0,16 Cu%+2e = Cu + 0,34 2H20+0O2+4e = 40H” +0,40 Cuv+e = Cu + 0,52 Agtt+e = Ag +0,80 Oo(g) + 4H*+4e° = 2H20 +423 Chkig)+2e7 = 2Ct + 1,36 10.1 Define the term reducing agent in terms of electron transfer. 10.2 From the above Table of Standard Reduction Potentials, write down the: 10.2.1 NAME or FORMULA of the strongest reducing agent 10.2.2 Oxidation half-reaction with the lowest oxidation potential 10.2.3 Reduction potential of the half-reaction in which Cr’*(aq) acts as reducing agent 10.3 A learner pours a copper(I!) sulphate solution into a zinc container. 10.3.1 Is a zinc container suitable to store a copper(II) sulphate solution? Choose from YES or NO. 10.3.2 Explain the answer to QUESTION 10.3.1 by referring to the above table. TOTAL: Copyright reserved UNA EASTERN CAPE (2) (1) (2) (1) (1) (3) {10} 150

Physical Sciences/P2 1. SC/NSC 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 DBE/November 2020(2) NAME/NAAM SYMBOL/SIMBOOL VALUE/WAARDE TABLE 2: FORMULAE/TABEL 2: FORMULES | om N n=— n=— M Ny n m Vv =f lof = n=— c V eee c MV V, CaNV0 Da H = -log[H.0* cv. on, pH = -log[H30*] Kw = [H30"][OH] = 1 x 10° atiby 298 K aay = Feathode ~ Erode / =a = Preise - EF enode orlof | ¢e () C) 8 t) 8 Een = Epduction ~ Eosdation! Eset = Ereduisie — Eotsidasie or/of 6 _pe 8 8 _ fe a) Eee ~ Eoadisingagent ~ E reducingagent 1B ee ~ E osideermiddel E reduseemiddel Copyright reserved I A EASTERN CAPE Please turn over

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Physical Sciences/P2 Increasing oxidising ability/ Toenemende oksiderende vermoé Copyright reserved 3, SC/NSC TABLE 4A: STANDARD REDUCTION POTENTIALS TABEL 4A: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E° (Vv) Fo(g)+2e = 2F + 2,87 Co*+e = Co™ + 1,81 H2Q2+ 2H" +2e7 = 2H2O 41,77 MnO] +8H*+5e> = Mn“ +4H,O | +1,51 Ch(g)+2e = 2Cr +1,36 CrO} +44H"+6e = 2Cr*+7HO | +1,33 O.(g)+4H* +4e" = 2H20 + 1,23 MnO2+ 4H* +2e° = Mn” + 2H0 + 1,23 Pt+2e . Pt + 1,20 Bro(t)+2e° = 2Br + 1,07 NO, +4H'+3e = NO(g)+2H,0 | +0,96 Hg**+2e = Hag(t) + 0,85 Agite = Ag +0,80 NO} +2H*+e = NO2(g)+H20 +0,80 Fe*+e = Fe™* +077 O2(g) + 2H*+2e = HO2 + 0,68 k+2e = 2b + 0,54 Cu’+e = Cu + 0,52 SO2+4H*+4e = S+2H20 +0,45 2H20+O2+4e7 = 40H” +0,40 Cu*+2e = Cu + 0,34 S04 +4H'+2e = S02(g)+2H20| +0,17 Cu*+e = Cu +0,16 Sn“*+2e = Sn* +0,15 S+2H*+2e = HeS(g) +0,14 2H*+2e = Helg) 0,00 Fe*+3e = Fe — 0,06 Pb**+2e = Pb -0,13 Sn**+2e = Sn ~0,14 Ni*+2e = Ni —0,27 Co” + 26° Co - 0,28 Cd**+2e = Cd - 0,40 Crt+e = Cr -0,41 Fe +2e = Fe ~ 0,44 cr+3e = Cr -0,74 Zn*+2e = Zn -0,76 2HO+2e" = Hg)+2O0H | -0,83 Crt+2e = Cr -0,91 Mn**+2e° = Mn -1,18 Abt +3e = At -1,66 Mg**+2e" = Mg - 2,36 Na’+e. = Na -2,71 Ca*+2e = Ca - 2,87 SPt+2e = Sr — 2,89 Ba**+2e = Ba — 2,90 Cs*+e = Cs - 2,92 Kite = K - 2,93 Lite - 3,05 = Li ASTERN CAPE DBE/November 2020(2) Increasing reducing ability/ Toenemende reduserende vermoé Please turn over

Physical Sciences/P2 Increasing oxidising ability/Toenemende oksiderende vermoé Copyright reserved 4. SC/NSC TABLE 4B: STANDARD REDUCTION POTENTIALS TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E® (v) lite a Li — 3,05 K'te =o K — 2,93 Cs*+e = Cs — 2,92 Ba*+2e = Ba - 2,90 Sr+2e = Sr — 2,89 Ca +2e° = Ca ~ 2,87 Na*+e7 = Na -2,71 Mg" +2e° = Mg — 2,36 Abt+3e° = AL — 1,66 Mn** + 26° Mn = 1,18 Ce +2e° = Cr -0,91 2H.0+2e = Hy(g)+20H” | -0,83 Zn*+2e = Zn — 0,76 Crt+3e° = Cr — 0,74 Fe*+2e = Fe ~ 0,44 crt+e = Cr -0,41 Cd**+2e° = Cd — 0,40 Co*+2e = Co - 0,28 Ni +2e- = Ni — 0,27 Sn*+2e = Sn 0,14 Pb” +2e° = Pb - 0,13 Fe*+3e = Fe — 0,06 2H*+2e° = Hag) 0,00 S+2H"+2e = HS(g) +0,14 Sn +2e = Sn* + 0,15 Cu%+e = Cur +0,16 S03 +4H*+2e° = SO2(g)+2H,0| +0,17 Cu*+2e = Cu + 0,34 2H20 +02+4e° = 40H +0,40 SQ.+4H’+4e° = S+2H0 + 0,45 Cu’+e™ = Cu + 0,52 b+2e = 2 + 0,54 O2(g) + 2H +2e7 = HzOQ2 + 0,68 Fe"+e = Fe™* +0,77 NO} +2H* +e NO2(g)+H20 | +0,80 Ag’+e = Ag + 0,80 Hg” +2e" = Hg() + 0,85 NO; +4H'+3e = NO(g)+2H20 | +0,96 Bro(f)+2e = 2Br +1,07 Pit+2e7 = Pt + 1,20 MnQ2+ 4H*+2e == Mn**+2H20 + 1,23 O.(g)+4H*+4e° = = 2H20 + 1,23 CrO? +44H'+6e = 2Cr*+7H20 | +14,33 Ci(g)+2e7 = 208 + 1,36 MnO, +8H*+5e7 = Mn +4HoO | +4,51 H202+2H*+2e° = 2H,O +1,77 Co* +e = Co* + 1,81 Fo(g)+2e = + 2,87 2F- EASTERN CAPE DBE/November 2020(2) Increasing reducing ability/Toenemende reduserende vermoé