Physical Sciences Grade 12 P2 Gauteng Mock 2021 QP (Eng)

basic education Department: Basic Education REPUBLIC OF SOUTH AFRICA SENIOR CERTIFICATE/ , NATIONAL SENIOR CERTIFICATE GRADE 12 PHYSICAL SCIENCES: CHEMISTRY (P2) NOVEMBER 2020(2) MARKS: 150 TIME: 3 hours PHYSICAL SCIENCES: Paper 2 A a 10842E. X10 IAT This question paper consists of 16 pages and 4 data sheets. Copyright reserved Please turn over

Physical Sciences/P2 2 DBE/November 2020(2) Downloaded from hlayiso.com SCINSC INSTRUCTIONS AND INFORMATION 1. 10. 11. 12. a 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 decimai places. Give brief motivations, discussions, etc. where required. You are advised to use the attached DATA SHEETS. Write neatly and legibly. Copriaht reserves (OMA ONAL A Please tun over GAUTENG

Downloaded from hlayiso.com Physical Sciences/P2 3. DBE/November 2020(2) SC/NSG QUESTION 1: MULTIPLE-CHOICE QUESTIONS 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. 1.1 Which ONE of the following is an ALKANE? A CeHe Bo CeHio C CeHi2 D CoHi4 (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 Hydroxy! 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 CHeCHCHs C CHsCH2CH3 D CHgCHCHCH3 (2) Conroe ML Pease wo

Downloaded from hlayiso.com Physical Sciences/P2 4. SC/NSC DBE/November 2020(2} 1.4 A hydrochloric acid solution, HC&(aq), of concentration 4 mold? 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. i n fon) a I = G ae 83 “ nome) ¢ 23/ / 1 52 2 * U € ‘ 3 p g i > Time Which ONE of the following represents the conditions used to obtain curve IL? STATE OF Division | CONCENTRATION | tempERATURE OF ACID ° OF Mg (mol-dm*) (°C) A | Ribbon 0,5 25 B | Ribbon 2 25 C | Powder 1 20 D | Powder 1 30 (2) 46 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 N2O4(g) = 2NO2(g) B -HA(g) + le(g) = 2HI(g) CG Na(g) + 3Ha(g) = 2NHa(g) D —28042(g) + O2(g) = 280s(9) (2) Copyright id Pl tt cmfonreene 0 ree oe

Downloaded from hlayiso.com Physical Sciences/P2 5. DBE/November 2020(2) SCINSG 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. HsPOx(aq) + H2O(2) = HgO*(aq) + H2PO; (aq) Which ONE of the following is a conjugate acid-base pair? A H30*(aq) and H20(f) B — H3PO.4(aq) and H20(£) C — -HsP0,(aq) and H30*(aq) D H30"(aa) 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) Conroe TTI TT rr

Downloaded from hlayiso.com Physical Sciences/P2 6. DBE/November 2020(2) SC/NSC 1.9 An electrochemical cell is set up at standard conditions. The cell notation for the cell is given below. Mg(s) | Mg**(aq) || P**(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? A ~ 4 B ~ 4 a % 3 3 Pb**(aq) E E §,{__Pe"'aq) § 8 Mg (aq) g' c < 8 8 2 £ 2 Mg?*(aq) co) oO > oO > Time (s) Time (s) Cc D x = f 2+ 6 9 Mi A os a g* (aq) 9 Mg*"(aq) 3 xe} re) S = 5 E rs 1 8 1 < =] 8 pb 8 8 a 5 Pb?*(aq) Ss) > o > Time (s) Time (s)} (2) 1.10 Two 50 kg bags, containing fertilisers R and S respectively, are labelled as follows: Fertiliser R: 3: 41:5 (20) Fertiliser S: 1:2: 6 (20) Identify the fertiliser(s) most suitable for healthy leaf growth and healthy root growth. LEAF GROWTH ROOT GROWTH A R R B iS R c R iS) D s s (2) [20] Copyright reserved CIMINO AATCC A Please tum over GAUTENG

Downloaded from hlayiso.com Physical Sciences/P2 7. DBE/November 2020(2) SC/NSG QUESTION 2 (Start on a new page.) The letters A to E in the table below represent five organic compounds. H Br CH3 CHsCHs A i B | C,H, I i ba, CH2CH3 H H H OH c| wd tt D | CHs(CH;)sCH(OH)CH2CHs fad od E | CHsCH2CH2CH2CH2CH2CHCH2 2.1 Write down the LETTER that represents EACH of the following: 21.1 Aketone (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: 2CyHy + 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] Cony esr LQ Pease mover

Downloaded from hlayiso.com Physical Sciences/P2 8. DBE/November 2020(2) SC/NSC 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 below. COMPOUND BOILING POINT (°C) A_ | Butan-1-ol 117 B_ | Butan-2-ol 100 C | 2-methylpropan-2-ol 82 3.1 Is this a fair investigation? Choose from YES or NO. (1) 3.2 Give a reason for the answer to QUESTION 3.1. (1) 3.3 Fully explain the difference in the boiling points of compounds B and C. (3) 3.4 Define the term positional isomer. (2) 3.5 From compounds A, B and C, choose the letter(s) that represent(s) EACH of the following: 3.5.1 Positional isomers (1) 3.5.2 A tertiary alcoho! Give a reason for the answer. (2) 3.6 The graph below represents the relationship between vapour pressure and temperature for compound A (butan-1-ol). 4 aS & A 2 i] n n oO a 5 8 xX beeen eee ee eens 4 J i > ‘ 117 . Temperature (°C) 3.6.1 Write down the vaiue of X. (1) 3.6.2 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. (2) [13] Comwieht reserves UITAAVAAAC TOU AU ALATA Please turnover GAUTENG

Downloaded from hlayiso.com Physical Sciences/P2 9. DBE/November 2020(2) SCINSC 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 > R > -1- Propane Bra Dilute NaOH Propan-1-ol T || Reaction 3 U Write down the NAME of the type of reaction represented by: 4.1.1 Reaction 1 (1) 4.1.2 Reaction 2 (1) Consider reaction 1 and reaction 2. 4.1.3 Write down the IUPAC name of compound R. (2) Reaction 3 takes place in the presence of a catalyst and heat. Write down the: 4.14 NAME or FORMULA of the catalyst (1) 4.15 IUPAC name of compound T (2) 4.1.6 STRUCTURAL FORMULA of compound U (2) Copter 100 Pee an over

Downloaded from hlayiso.com Physical Sciences/P2 10. DBE/November 2020(2) SC/NSC 4.2 A laboratory technician wants to prepare but-2-ene using but-1-ene as starting reagent, as shown below. H H HT O= 6-66 # ————————> _ But-2-ene H H H The following chemicals are available in the laboratory: [concentrated H2SO,__| H2O [ 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 chemicals needed in each step. QUESTION 5 (Start on a new page.) organic compounds. Indicate the 5.1 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 5.1.2 Q 5.2 Line R represents the minimum energy required for the reaction to take place. 5.2.1 Write down the term for the underlined phrase. §.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. 5.3 Use the collision theory to explain how a catalyst influences the rate of reaction. Copyright reserved Please turn over GAUTENG (6) [15] (1) (1) (1) (1) (4)

Downloaded from hlayiso.com Physical Sciences/P2 11. DBE/November 2020(2) SC/NSC 5.4 The reaction between POWDERED calcium carbonate, CaCOa(s), and EXCESS hydrochloric acid, HCf(aq), is used to investigate reaction rate at 25 °C. The balanced equation for the reaction is: CaCOa(s) + 2HCf(aq) + CaCfa(aq) + H2O(2) + 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 60 1 a oO i oN =) w oO (cm*-min) nN i=} = oO Average rate of production of CO2 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 (1) 5.4.2 Conclusion (2) 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’. (6) [17] Conse A QL] Ps o ahs

Downloaded from hlayiso.com Physical Sciences/P2 12. DBE/November 2020(2) SC/NSC QUESTION 6 (Start on a new page.) Steam, H2O(g), reacts with hot carbon, C(s), at 1000 °C according to the following _ balanced equation: 2H20(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. 6.2 Calculate the equilibrium constant, Ke, for the reaction at 1 000 °C. 6.3 The graph shows how the rates of the forward and reverse reactions change with time. a — Forward reaction -~- Reverse reaction Rate to th te ts Time 6.3.1 Give a reason why the rate of the forward reaction decreases between ty and ty. 6.3.2 What change was made to the equilibrium mixture at ts? At time t, the temperature of the system is increased. 6.3.3 Is the forward reaction EXOTHERMIC or ENDOTHERMIC? 6.3.4 Refer to Le Chatelier’s principle. to explain the answer to QUESTION 6.3.3. Coord TT (2) (8) (1) (1) (2) [15]

Downloaded from hlayiso.com Physical Sciences/P2 13. DBE/November 2020(2) SC/INSC 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> 7A 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. fo —™ c A B . 3 0,1 mol-dm? Ba(OH),(aq) | 500 cm pH = 13 400 cm? | KOH(aq) Demmeaeeeaes omnia 7.3.1 Calculate the concentration, X, of the Ba(OH)> 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: CHsCOOH(aq) + OH"(aq) -» CH,COO™ (aq) + H20(2) 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] Conon EN Pease am oe

Downloaded from hlayiso.com 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) | ¥ 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(II) ions is changed to 0,6 mol-dm®? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) [14] Copa ese OH Peas oe

Downloaded from hlayiso.com Physical Sciences/P2 15. DBE/November 2020(2) SC/NSC 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. DC source +——Impure copper Electrolyte | __s, 9.1 Define the term efectrolysis. (2) 9.2 Write down the NAME or FORMULA of TWO positive ions present in the electrolyte. (2) 9.3 Write down the half-reaction that takes place at the cathode. (2) 9.4 Refer to the Table of Standard Reduction Potentials and explain why the purified copper will NOT contain any zinc. (3) 9.5 Calculate the maximum mass of Cu formed if 0,6 moles of electrons are transferred. (3) [12] Contes A 0 0 0 esse an oe

Downloaded from hlayiso.com Physical Sciences/P2 16. DBE/November 2020(2) SC/NSC QUESTION 10 (Start on a new page.) 10.1 10.2 Copyright reserved The flow diagram below shows processes involved in the production of fertiliser C. Gas A Haber process "Compound B -H2S80s8@9),! Fertiliser ¢ He(g) Write down the NAME or FORMULA of: Gas A (1) The catalyst used in the Haber process (1) Compound B (1) Write down the: Name of the process used to produce gas A (1) Balanced equation for the formation of fertiliser C (3) A 40 kg bag of fertiliser contains 65% filler. The mass ofthe nutrients in the bag is shown in the table below. NUTRIENTS MASS (kg) Nitrogen x Phosphorous 2x Potassium 5 Calculate the NPK ratio of the fertiliser. (3) [10] TOTAL: 150 GAUTENG

Downloaded from hlayiso.com Physical Sciences/P2 4 DBE/November 2020(2) SCINSC 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 NAME/NAAM SYMBOL/SIMBOOL VALUE/WAARDE TABLE 2: FORMULAE/TABEL 2: FORMULES n=™ n= M Na c=) orfof c= n= Vv MV Vin Ca = na _ + Cy My pH = -log[H30] Kw = [HsO*][OH7] = 1 x 10° at/by 298 K 8 _ Fe t] 8 re Q Eee ~ Eeathode 7 Enode ES ~ Eatode ~ E node or/of @ _-e _ pe 8 68 ry Eee 7 Eesuction E Sedation! Eset ~ Eautsie ~ eosidasie orlof 6 _ pe _ fe e@ fe 8 een ~~ Ee caisingagent Eeaueingagent (Ea ~ E cyeideemidde! ~ Feequecermiddet Copyright reserved UMA EO AE Please turn over

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Physical Sciences/P2 Increasing oxidising ability/Toenemende oksiderende vermoé Copyright reserved Downloaded from hlayiso.com 3 SC/NSC TABLE 4A: STANDARD REDUCTION POTENTIALS TABEL 4A: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E® (v) Fog) +26 = 2F + 2,87 Co +e = Co* +1,81 H2Qz2 + 2H* +2e7 2H20 +1,77 MnO, +8H*+5e = Mn +4H,O | +1,51 Chg) +#2e = 2Cr + 1,36 C02 + 14H +607 = 20+ 7H | 41,33 O2.(g) + 4H" +4e° = 2H20 + 1,23 MnQ2+ 4H" +2e” = Mn?" + 2H20 + 1,23 Pi*+2e = Pt + 1,20 Bro(t)+2e = 2Br + 1,07 NO; +4H" +3e7 NO(g) + 2H20 | + 0,96 Hg”* + 267 Hg(t) + 0,85 Agte = Ag + 0,80 NO} +2H7+e = NOx(g)+H2O |} +0,80 Fe"+e = Fe* +0,77 Ox(g) + 2H*+2e = H2O2 + 0,68 +207 = ar +0,54 Cu*+e = Cu + 0,52 $Q.+4H*+4e" = S+2H,0 + 0,45 2H20 + O2+4e = 40H" +0,40 Cu +2e7 = Cu + 0,34 S07 +4H*+2e" = SO2(g)+2H20 | +0,17 Cu +e we Cur +0,16 Sn“*+2e = Sn* +0,15 S+2H'+2e = HS(g) + 0,14 2H*+2e- = Hha(g) 0,00 Fe*+3e = Fe — 0,06 Pb +2e° = Pb -0,13 Sn*+2e = Sn -0,14 Ni*+2e7 = Ni - 0,27 Co%*+2e = Co ~ 0,28 Cd*+2e7 = Cd -0,40 cette = Cr -0,41 Fe" +207 = Fe - 0,44 crt+3e7 = Cr -0,74 Zn*+2e = Zn ~ 0,76 2H2O+2e w= Ho(g)+2OH | -0,83 Cre'+2e = Cr -0,91 Mn®+2e7 = Mn = 1,18 AC +3e = Ad — 1,66 Mg" +2e = Mg - 2,36 Na’+e" = Na -2,71 Ca™* + 2e7 Ca — 2,87 Sv+2e = Sr - 2,89 Ba**+2e = Ba - 2,90 Cs'+e = Cs - 2,92 Kite K - 2,93 Lite = L - 3,05 GAUTEN! cy DBE/November 2020(2) Increasing reducing ability/Toenemende reduserende vermoé Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 4. DBE/November 2020(2) SC/NSC TABLE 4B: STANDARD REDUCTION POTENTIALS TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E® (vy) lite a Li ~ 3,05 Kite = K = 2,93 Cs*+e = Cs — 2,92 Ba**+2e = Ba - 2,90 Sr+2e = Sr 2,89 Ca +2e = Ca - 2,87 Na*+e = Na -2,71 Mg” +2e7 = Mg — 2,36 AB*+3e° = AL - 1,66 4 Mn**+2e7 = Mn —1,18 10 Cr*+2e = Cr -0,91 2 2H,0+2e" = Halg)+20H" | -0,83 3 Zn*+2e = Zn - 0,76 ‘9 3 cr*+3e = Cr - 0,74 —E 3 Fe +20" a Fe -0,44 $ ¢ crt+e = Crt -041 ® 3 Cd*+2e7 =. Cd -0,40 3 a Co* +20 = Co — 0,28 eg $ N@+2e° = Ni ~ 0,27 & 2 Sn*+2e7 = Sn 014 3 § Pb*+2e7 = Pb 0,13 £ 3 Fe*+3e7 = Fe = 0,06 g 2 2H"+2e7 = Hag) 0,00 5 2 $+2H'+2e° = H,S(Q) +014 5 > sn 4+2e . Sn + 0,15 5 = Cu* +e = Cut + 0,16 ec a 803° +4H*+2e" = SOx(g)+2H,0| +0,17 > > Cu*+2e7 = Cu + 0,34 5 ‘oO 2H20+O2+4e" = 4OH™ + 0,40 CI kj SQ.+4H'+4e° 2 S+2H0 +0,45 > 3 Cuu+e = Cu + 0,52 3 =) lbt2e = ot + 0,54 3 O O2(g)+2H*+2e° w= H2O2 + 0,68 = g Fe +e" = Fe +0,77 > S NO3 +2H*+e" & NOx(g)+H:0 | +0,80 8 ~ Ag’t+e = Ag +0,80 5 Hg? +2e7 2 Ha(t) + 0,85 £ NOZ +4H'+3e = NO(g)+2H,0 | +0,96 Br(t)+2e° = 28r + 1,07 PO +2e a Pt + 1,20 MnOz+4H*+2e- = Mn*+2H2.O | +1,23 O.(g)+4H'+4e7° = 2H20 + 1,23 CrOF +14H"+6e> = 2Cr*+7H,0 | + 1,33 Ch(g)+2e° = 2Cr + 1,36 MnO4 +8H*+5e" = Mn*+4h20 | + 4,51 H2Q2+2H*+2e° = 2H2O W177 Co*#e «= Co* + 1,81 Fo(g)+2e° = + 2,87 2F- copriatecred TITAN ATA AT