Physical Sciences Grade 12 P2 Eastern Cape June 2023 Memo

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE/ NASIONALE SENIORSERTIFIKAAT GRADE/GRAAD 12 JUNE/JUNIE 2023 PHYSICAL SCIENCES: CHEMISTRY P2 MARKING GUIDELINE/ FISIESE WETENSKAPPE: CHEMIE V2 NASIENRIGLYN MARKS/PUNTE: 150 This marking guideline consists of 17 pages./ Hierdie nasienriglyn bestaan uit 17 bladsye.

Downloaded from hlayiso.com 2 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/JUNE/JUNIE 2023) QUESTION 1/VRAAG 1 1.1 C  (2) 1.2 B  (2) 1.3 B  (2) 1.4 B  (2) 1.5 A  (2) 1.6 C  (2) 1.7 D  (2) 1.8 C  (2) 1.9 B  (2) 1.10 B  (2) [20] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com (EC/JUNE/JUNIE 2023) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 3 QUESTION 2/VRAAG 2 2.1 2.1.1 H (1) 2.1.2 D (1) 2.1.3 A (1) 2.1.4 F (1) 2.1.5 F (1) Marking criteria/Nasienkriteria If any of the underlined key words/phrases in the correct context are omitted: - 1 mark per word/phrase. Indien enige van die sleutelwoorde/frases in die korrekte konteks weggelaat word: - 1 punt per woord/frase. 2.2 2.2.1 Compounds that have the same molecular formula but different structural formulae.  Verbindings wat dieselfde molekulêre formule maar verskillende struktuurformules het. (2) 2.2.2 POSITIONAL / POSISIONEEL  (1) 2.2.3 SECONDARY / SEKONDÊR  The C bonded to OH is bonded to two other carbons/ C of functional group bonded to two other carbons / C bonded to OH has 1 hydrogen/ C of functional group has one hydrogen  Die C wat verbind is aan die OH is verbind aan twee ander koolstowwe / C van die funksionele groep is verbind aan twee ander koolstowwe / C wat verbind is aan die OH het 1 waterstof / C van die funksionele groep het 1 waterstof. (3) Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com 4 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/JUNE/JUNIE 2023) 2.3.1 3,4-dimethylhept-3-ene / 3,4-dimethylhept-3-ene 3,4-dimetielhept-3-een / 3,4-dimetiel-3-hepteen Marking criteria/Nasienkriteria: • Heptene / Hept-een  • Dimethyl / dimetiel  • Whole name correct / hele naam korrek  (3) 2.3.2 Marking criteria/Nasienkriteria: O • Whole structure correct/Hele struktuur korrek: 2/2 • Only functional group correct CH3 CH2 CH  Slegs funksionele groep korrek Max./Maks. 1/2 OR / OF CH3CH2CHO  (2) 2.4.1 C2H4O  (1) 2.4.2 Carboxyl (group) / Karboksiel (groep)  (1) 2.5.1 Ester  (1) 2.5.2 Methyl butanoate  / Metiel butanoaat H H H O H  H C C C C O C H  H H H H H Marking criteria/Nasienkriteria • Functional group/Funksionele groep  1/2 • Whole structure correct/ Hele struktuur korrek  2/2 (4) [23] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com (EC/JUNE/JUNIE 2023) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 5 QUESTION 3/VRAAG 3 Marking criteria/Nasienkriteria If any of the underlined key words/phrases in the correct context are omitted: - 1 mark per word/phrase. Indien enige van die sleutelwoorde/frases in die korrekte konteks weggelaat word: - 1 punt per woord/frase. 3.1 Melting point is the temperature at which the solid and liquid substances are at equilibrium.  Smeltpunt is die temperatuur waarby die vastof- en vloeistoffases van ʼn stof in ewewig is. (2) 3.2 Marking criteria • Increase in molecular size from A to C • Increase in molecular size leads to increase in the strength of the London forces/Dispersion forces/Induced dipole forces • Relate the strength of London forces /dispersion forces/induced dipole to energy involved. Nasienkriteria • Toename in molekulêre grootte vanaf A na C • Toename in molekulêre grootte lei na ʼn toename in die sterkte van die Londonkragte/verspreidingskragte/geїnduseerde dipoolkragte • Verwys die sterktes van Londonkragte/Verspreidingskragte/ Geїnduseerde dipoolkragte met energie betrokke. From A to C / Vanaf A na C • Surface area/molecular size/chain length increases  • Strength of London forces/dispersion forces/induced dipole forces increases  • More energy is needed to overcome intermolecular forces  • Oppervlakte/molekulêre grootte/kettinglengte neem toe • Sterkte van die Londonkragte/verspreidingskragte/geїnduseerde dipoolkragte neem toe • Meer energie word benodig om die intermolekulêrekragte te oorkom OR/OF Marking criteria • Decrease in molecular size from C to A • Decrease in molecular size leads to decrease in the strength of the London forces/dispersion forces/induced dipole forces • Relate the strength of London forces to energy involved. Nasienkriteria • Afname in molekulêre grootte vanaf C na A • Afname in molekulêre grootte lei na ʼn afname in die sterkte van die Londonkragte/verspreidingskragte/geїnduseerde dipoolkragte • Verwys die sterktes van Londonkragte/verspreidingskragte/ geїnduseerde dipoolkragte met energie betrokke Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com 6 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/JUNE/JUNIE 2023) From C to A / Vanaf C na A • Surface area/molecular size/chain length decreases  • Strength of London forces/Dispersion forces/Induced dipole forces decreases  • Less energy needed to overcome intermolecular forces  • Oppervlakte/ molekulêre grootte/ kettinglengte neem af • Sterkte van Londonkragte/verspreidingskragte/geїnduseerde dipoolkragte neem af • Minder energie word benodig om die intermolekulêrekragte te oorkom (3) 3.3 A / Propane / Propaan  Lowest melting point / Laagste smeltpunt  (2) 3.4 3.4.1 Marking criteria/Nasienriglyne H H H H • 4 Carbons in longest chain  ½ H C C C C H  4 koolstowwe in die langste ketting ½ H H H • Whole structure correct 2/2  Hele struktuur korrek 2/2 H C H H (2) 3.4.2 LESS THAN / MINDER AS - 129 °C  (1) 3.4.3 Yes / Ja  Compounds C and D have the same molecular mass/chain isomers  Verbindings C en D het dieselfde molekulêremassa/ketting-isomere. (2) Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com (EC/JUNE/JUNIE 2023) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 7 3.5 Marking criteria • E has dipole-dipole forces • F has hydrogen bonds • Correctly compare the strength of hydrogen bonds to dipole-dipole forces • Relate the strength of the intermolecular forces to energy involved. Nasienkriteria • E het dipool-dipoolkragte • F het waterstofbindings • Vergelyk die sterkte van die waterstofbindings korrek aan die dipool- dipoolkragte • Verwys die sterktes van intermolekulêrekragte met energie betrokke • F has hydrogen bonds  (and London forces) • E has dipole-dipole forces  (and London forces) • Hydrogen bonds are stronger than dipole-dipole forces  • More energy is needed to overcome intermolecular forces in E  • F het waterstofbindings (en Londonkragte) • E het dipool-dipoolkragte (en Londonkragte) • Waterstofbinding is sterker as dipool-dipoolkragte • Meer energie word benodig om die intermolekulêrekragte te oorkom OR/OF Marking criteria • E has dipole-dipole forces • F has hydrogen bonds • Correctly compare the strength of hydrogen bonds to dipole-dipole forces • Relate the strength of the intermolecular forces to energy involved Nasienkriteria • E het dipool-dipoolkragte • F het waterstofbindings • Vergelyk die sterkte van die waterstofbindings korrek aan die dipool- dipoolkragte • Verwys die sterktes van intermolekulêrekragte met energie betrokke • F has hydrogen bonds  (and London forces) • E has dipole-dipole forces  (and London forces) • Dipole-dipole forces are weaker than hydrogen bonds  • Less energy is needed to overcome intermolecular forces in F  • F het waterstofbindings (en Londonkragte) • E het dipool-dipoolkragte (en Londonkragte) • Dipool-dipoolkragte is swakker as waterstofbinding • Minder energie word benodig om die intermolekulêrekragte in F te oorkom (4) [16] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com 8 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/JUNE/JUNIE 2023) QUESTION 4/VRAAG 4 4.1 4.1.1 Alcohol / Alkohol  (1) 4.1.2 (Mild) heat / dilute base / (Matige) hitte / verdunde basis  (1) 4.1.3 H2O/KOH/NaOH/LiOH  (1) 4.1.4 Dehydration/Dehidrasie / dehidratering/dehidrerend  (1) 4.1.5 Marking criteria/Nasienkriteria: Organic compounds only • Functional group/Funksionele groep.  1/2 • Whole structure correct/ Hele struktuur korrek  2/2 H H  H H H H Conc H2SO4   H C C C O H C C C H H H H H H H + H2O  (6) 4.1.6 Addition  or halogenation and hydrohalogenation  Addisie of halogenering en hidrohalogenering (1) 4.1.7 HBr  (1) 4.1.8 1,2-dibromopropane  Marking criteria/Nasienkriteria 1,2-dibromopropaan • Functional group (2 Br atoms)/Funksionele groep.  1/2 • Whole structure correct/ Hele struktuur korrek  2/2 Br  Br H H C C C H H H H (4) 4.2 4.2.1 Breaking down of long chain hydrocarbon molecules into more useful shorter chains  (2 or 0) Afbreek van langer koolwaterstof-molekules in korter meer gebruikbare molekules (2 of 0) (2) Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com (EC/JUNE/JUNIE 2023) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 9 4.2.2 Marking criteria/Nasienkriteria: • Identifying compound Q / Identifisering van verbinding Q • Identifying CxH6 / Identifisering van CxH6 • Identifying compound P / Identifisering van verbinding P • Reactants / Reaktanse • Products / Produkte • Balancing / Balansering Q = C2H4  CxH6 = C3H6  P = C8H18  2 C8H18 + 25 O2  16 CO2 + 18H2O   Bal. (6) [24] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com 10 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/JUNE/JUNIE 2023) QUESTION 5/VRAAG 5 5.1 Marking criteria/Nasienkriteria If any of the underlined key words/phrases in the correct context are omitted: - 1 mark per word/phrase. Indien enige van die sleutelwoorde/frases in die korrekte konteks weggelaat word: - 1 punt per woord/frase ANY ONE Change in concentration ✓of reactant or product per (unit) time. ✓ Change in amount/number of moles/volume/mass ✓of products or reactants per (unit) time. ✓ Change in amount/number of moles/volume/mass ✓ of products formed or reactants used reactants per (unit) time. ✓ ENIGE EEN Verandering in konsentrasie van reaktanse of produkte per (eenheid) tyd. Verandering in hoeveelheid/getal mol/volume/massa van reaktanse of produkte per (eenheid) tyd. Verandering in hoeveelheid/getal mol/volume/massa van produkte gevorm/reaktanse gebruik per (eenheid) tyd. OR/OF The rate of change in concentration/amount of moles/number of moles / volume / mass. ✓✓ (2 or 0) Die tempo van verandering in konsentrasie/hoeveelheid mol/getal mol/volume/massa ✓✓ (2 of 0) (2) 5.2 Marking criteria /Nasienkriteria Both variables correctly identified/ Beide veranderlike korrek geïdentifiseer (1/2) Question relates dependent and independent variables/ Vraag toon die verband tussen die afhanklike en onafhanklike veranderlike (1/2) What is the relationship between concentration and reaction rate? ✓✓ OR How does concentration affect reaction rate? Wat is die verhouding tussen konsentrasie en reaksietempo? OF Hoe affekteer konsentrasie die reaksietempo? (2) 5.3 Sulphur / Swawel  (1) 5.4 There must be ONE independent variable ✓/ The size of the cross is a control variable Daar moet slegs EEN onafhanklike veranderlike wees. / Die grootte van die kruis is ʼn beheerde veranderlike. (1) Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com (EC/JUNE/JUNIE 2023) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 11 5.5 Higher concentration • More particles per unit volume  • More particles collide with correct orientation  • Frequency of effective collisions increases /More effective collisions per unit time  Hoër konsentrasie • Meer deeltjies per eenheid volume • Meer deeltjies bots teen die korrekte oriëntasie • Frekwensie vir effektiewe botsings neem toe/Meer effektiewe botsings per eenheid tyd OR/ OF Lower concentration • Fewer particles per unit volume  • Fewer particles collide with correct orientation  • Frequency of effective collisions decreases/Fewer effective collisions per unit time  Lae konsentrasie • Minder deeltjies per eenheid volume • Minder deeltjies bots teen die korrekte oriëntasie • Frekwensie vir effektiewe botsings neem af/Minder effektiewe botsings per eenheid tyd (3) 5.6 Marking criteria/Nasienkriteria • Reading the correct concentration of Na2S2O3/Korrekte lesing van die konsentrasie van Na2S2O3 • Subst. into/Vervanging in n = cV • Using the mol ratio/Gebruik van mol verhouding Na2S2O3 : S • Formula/Formule m = nM • Subst. into/Vervanging m = nM • Final answer/Finale antwoord c (Na2S2O3) = 0,125 mol·dm-3  n(Na2S2O3) = cV = 0,125 x 50/1000  = 6,25 x 10-3 mol n(Na2S2O3) = n(S) = 6,25 x 10-3 mol  m = nM  = 6,25 x 10-3 x 32  = 0,2 g  (6) 5.7 5.7.1 Number of particles/molecules / Aantal deeltjies/molekules  (1) Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com 12 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/JUNE/JUNIE 2023) 5.7.2 Marking criteria / Nasienkriteria • Shape of / Vorm van B • Peak of B lower / Piek van B A laer  Q NOTE: A or B must be indicated B LET WEL: A of B moet aangedui word Kinetic energy / Kinetiese energie (2) [18] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com (EC/JUNE/JUNIE 2023) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 13 QUESTION 6/VRAAG 6 6.1 Marking criteria/ Nasienkriteria If any of the underlined key words/phrases in the correct context are omitted: - 1 mark per word/phrase. Indien enige van die sleutelwoorde/frases in die korrekte konteks weggelaat word: - 1 punt per woord/frase 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.  Wanneer die ewewig in ʼn geslote sisteem versteur word, sal die sisteem ʼn nuwe ewewig instel deur die reaksie te bevoordeel wat die versteuring teenwerk. (2) 6.2 Closed system / container / Geslote sisteem/houer (1) 6.3 6.3.1 OPTION 1: MOLE CALCULATIONS/ a. Substitute into n = m/M ✓ b. Determine Δn = 2x ✓ c. Correct ratio PCℓ5 : PCℓ3 : Cℓ2 ✓ d. Divide the equilibrium md by 2 dm3 ✓ e. Correct KC expression (formulae in square brackets) ✓ f. Substitution into the correct equilibrium expressions (KC) ✓ OPSIE 1: MOL BEREKENINGE a. Vervanging n = m/M ✓ b. Bepaal Δn = 2x ✓ c. Korrekte verhouding PCℓ5 : PCℓ3 : Cℓ2 ✓ d. Deel deur 2 dm3 ✓ e. Korrekte Kc uitdrukking (formule met viekant hakkies) ✓ f. Vervanging in korrekte Kc uitdrukking ✓ m n = M 83,4 n = (a) ✓ 208,5 n = 0,4 mol Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com 14 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/JUNE/JUNIE 2023) Δn (PCℓ5) = (x)(2) = 2x ✓ (b) PCℓ5 PCℓ3 Cℓ2 Initial mol 0,4 - Change in mol -2x +2x 2x ✓ (c) Equilibrium mol 0,4-2x 2x 2x 0,4-2x / 2 2x / 2 2x / 2 ✓ (d) Concentration 0,2 – x x x [PCℓ3][ Cℓ2] Kc = (e) ✓ [PCℓ5] (x)(x) Kc = (f) ✓ (0,2 – x) x2 Kc = 0,2 - x (6) 6.3.1 OPTION/OPSIE 2: CONCENTRATION CALCULATIONS/KONSENTRASIE BEREKENINGE a. Substitute into n = m/M ✓ b. Substitute into c = n/V ✓ c. Correct ratio PCℓ5 : PCℓ3 : Cℓ2 ✓ d. Equilibrium conc correct ✓ e. Correct KC expression (formulae in square brackets) ✓ f. Substitution into the correct equilibrium expressions (KC) ✓ n = m/M = 83,4/208,5 (a) ✓ = 0,4 mol ci (PCℓ5) = n/V = 0,4/2 (b) ✓ =0,2 mol.dm-3 PCℓ5 PCℓ3 Cℓ2 Initial - 0,2 concentration Change in +x ✓ (c) -x x concentration Equilibrium x ✓ (d) 0,2-x x concentration [PCℓ3][ Cℓ2] Kc = (e) ✓ [PCℓ5] (x)(x) Kc = (f) ✓ (0,2 – x) x2 Kc = 0,2 – x Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com (EC/JUNE/JUNIE 2023) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 15 6.3.2 Marking criteria/Nasienkriteria • Determine the value of x / Bepaal die waarde van x • Subst. into Kc expression / Vervanging in Kc uitdrukking 0,2 – x = 0,001  x = 0,1999 Kc = x2/ (0,2 – x) = 0,1992/(0,001)  = 39,601 (2) 6.3.3 HIGH YIELD / HOЁ OPBRENGS  Kc > 1/ Kc is large / groot  (2) 6.4 6.4.1 NO EFFECT/ GEEN EFFEK  (1) 6.4.2 DECREASES / VERLAAG  (1) 6.5 6.5.1 Equilibrium/ Stage where rate of forward reaction equals rate of reverse reaction  Ewewig / die plek waar die tempo van die voorwaartse reaksie gelyk is aan die tempo van die terugwaartse reakse. (1) 6.5.2 HEATED / VERHIT  (1) 6.5.3 • Increase in temperature favours the endothermic reaction.  • Concentration of PCℓ5 decreases while concentration of Cℓ2 increases  • The forward reaction was favoured/ equilibrium position shifted towards the right  • Toename in temperatuur bevoordeel die endotermiese reaksie. • Konsentrasie PCℓ5 neem af terwyl die konsentrasie van Cℓ2 toe neem • Die voorwaartse reaksie word bevoordeel/ ewewigsposisie verksuif regs. (3) [20] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com 16 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/JUNE/JUNIE 2023) QUESTION 7/VRAAG 7 7.1 7.1.1 A substance that forms hydrogen ions (H+)/ hydronium ions (H3O+) in water  ʼn Stof wat waterstofione (H+)/hydroniumione (H3O+) in water vorm (2) 7.1.2 Good electrical conductor / Inert  Goeie elektriese geleidingsvermoë / Inert (1) 7.1.3 CH3COOH  Higher ammeter reading / Hoër ammeterlesing Undergoes higher degree of ionisation / Ondergaan ʼn hoër graad van ionisasie  Higher concentration of ions in solution / Hoër konsentrasie van ione in die oplossing  (3) 7.1.4 H2O and/ en HCO3̄  (2) 7.1.5 CO32-  (1) 7.2 7.2.1 Reaction of a salt with water  (2 or 0) Reaksie van ʼn sout met water (2 of 0) (2) 7.2.2 ACIDIC / SUUR  NH4+ + H2O  NH3 + H3O+  (reactants and products) / (reaktanse en produkte) Excess H3O+ are formed / Oormaat H3O+ vorm  (4) 7.3 7.3.1 pH = - log [H3O+]  = - log 1  =0 (3) 7.3.2 n = cV  = 1 x 250/1000  = 0,25 mol  (3) Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com (EC/JUNE/JUNIE 2023) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 17 7.3.3 Positive marking from 7.3.2/ Positiewe nasien vanaf 7.3.2 Marking criteria/Nasienkriteria • Formula / Formule n = cV • Subst. of NaOH conc. and vol. into/ Vervanging van NaOH kons. En vol. in n = cV • Mol ratio / Mol verhouding NaOH : HCℓ • Subtract initial mol (from 7.3.2) from mol reacting with NaOH / Aftrek van aanvanklike mole (vanaf 7.3.2) van regerende mol NaOH • Mol ratio / Mol verhouding CaCO3 : HCℓ • Subst. into / Vervanging in m = nM for CaCO3 • Multiply mass of/ Vermenigvuldig massa van CaCO3 by/met 100/99,3 • Final answer/ Finale antwoord n(NaOH) = cV  = 0,5x 103/1000  = 0,0515 mol n (HCℓ reacting with / reageer met NaOH) = 0,0515 mol  n (HCℓ reacting with / reageer met CaCO3) = 0,25 – 0,0515  n (HCℓ reacting with / reageer met CaCO3) = 0,1985 mol n(CaCO3) = ½ (0,1985)  n(CaCO3) = 0,09925 mol m(CaCO3)= nM = 0,0925 x 100  = 9,925 g m = 9,925 x 100/99,3  m = 9,99 g  (RANGE / GEBIED: 9,99 to 10,07 g) (8) [29] TOTAL/TOTAAL: 150 Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief