Technical Sciences Grade 12 Paper 2 NSC November 2022 Memo

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE/ NASIONALE SENIOR SERTIFIKAAT GRADE/GRAAD 12 TECHNICAL SCIENCES P2/ TEGNIESE WETENSKAPPE V2 NOVEMBER 2022 MARKING GUIDELINES/NASIENRIGLYNE MARKS/PUNTE: 75 These marking guidelines consist of 7 pages. Hierdie nasienriglyne bestaan uit 7 bladsye. Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com Technical Sciences/P2/Tegniese Wetenskappe/V2 2 DBE/November 2022 NSC/NSS – Marking Guidelines/Nasienriglyne QUESTION/VRAAG 1 1.1 C  (2) 1.2 C  (2) 1.3 A  (2) 1.4 B  (2) 1.5 D  (2) [10] QUESTION/VRAAG 2 2.1 A series of organic compounds that are described by the same general formula  and where each member differs from the next by a CH2 group.  'n Reeks organiese verbindings wat deur dieselfde algemene formule beskryf kan word en waar elke lid van die volgende verskil deur 'n CH2-groep. (2) 2.2.1 A (1) 2.2.2 B and/en C  (NOTE/LET WEL: 2 or/of 0. Both letters should be indicated/Beide letters moet aangedui word) (2) 2.2.3 D (1) 2.2.4 F (1) 2.3 Butane/Butaan  (NOTE/LET WEL: 2 or/of 0) (2) 2.4.1 Marking criteria/Nasienkriteria:    Correct functional group  Whole structure correct  If a bond or hydrogen is missing ½  Korrekte funksionele groep  Volledige struktuur korrek  Indien binding of waterstof uitgelaat is, ½ (2) 2.4.2  H H (2) [13] C C H H Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com Technical Sciences/P2/Tegniese Wetenskappe/V2 3 DBE/November 2022 NSC/NSS – Marking Guidelines/Nasienriglyne QUESTION/VRAAG 3 3.1 The temperature at which the vapour pressure is equal to the atmospheric pressure.  Die temperatuur waar die dampdruk aan die atmosferiese druk gelyk is.  (2) 3.2 C (1) 3.3.1 Propanoic acid/Propanoësuur  3.3.2 Propan-1-ol/Propaan-1-ol  3.3.3 Propanal/Propanaal  (3) 3.4  Both propanoic acid and propan-1-ol/compounds A and B contain hydrogen bonds (in addition to London and dipole-dipole forces).   Propanoic acid/Compound A has (two sites) to form stronger intermolecular forces/hydrogen bonds than propan-1-ol (compound B) which has (only one site).   More energy is needed to overcome (stronger) hydrogen bonds/ intermolecular forces in propanoic acid/compound A than the (weaker) hydrogen bonds/intermolecular forces in propan-1-ol (compound B).   Thus, propanoic acid/compound A has a lower vapour pressure than propan-1-ol (compound B).   Beide propanoësuur en propaan-1-ol/verbindings A en B bevat waterstofbindings (bykomend tot London- en dipool-dipool-kragte).  Propanoësuur/Verbinding A het (twee gebiede om) sterker intermolukulêre kragte/waterstofbindings (te vorm) as propaan-1-ol (verbinding B) (wat net een gebied het).  Meer energie word benodig om (sterker) waterstofbindings/intermolekulêre kragte in propanoësuur/verbinding A te oorkom as die (swakker) waterstofbindings/intermolekulêre kragte in propaan-1-ol (verbinding B).  Dus, propanoësuur/verbinding A het 'n laer dampdruk as propaan-1-ol (verbinding B). OR/OF Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com Technical Sciences/P2/Tegniese Wetenskappe/V2 4 DBE/November 2022 NSC/NSS – Marking Guidelines/Nasienriglyne  Both propanoic acid and propan-1-ol/compounds A and B contain hydrogen bonds (in addition to London and dipole-dipole forces).  Propan-1-ol/Compound B has (only one site) to form weaker intermolecular forces/hydrogen bonds than propanoic acid (compound A) which has (two sites).  Less energy is needed to overcome (weaker) hydrogen bonds/intermolecular forces in propan-1-ol/compound B than the (stronger) hydrogen bonds/intermolecular forces in propanoic acid (compound A).  Thus, propan-1-ol/compound B has a higher vapour pressure than propanoic acid (compound A).  Beide propanoësuur en propaan-1-ol/verbindings A en B bevat waterstofbindings (bykomend tot London- en dipool-dipool-kragte).  Propaan-1-ol/Verbinding B het (slegs een gebied) om swakker intermolukulêre kragte/waterstofbindings te vorm as propanoësuur (verbinding A), wat (twee gebiede het).  Minder energie word benodig om (swakker) waterstofbindings/ intermolekulêre kragte in propaan-1-ol/verbinding B te oorkom as die (sterker) waterstofbindings/intermolekulêre kragte in propanoësuur (verbinding A).  Dus, propaan-1-ol/verbinding B het 'n hoër dampdruk as propanoësuur (verbinding A). (4) 3.5 A (1) [11] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com Technical Sciences/P2/Tegniese Wetenskappe/V2 5 DBE/November 2022 NSC/NSS – Marking Guidelines/Nasienriglyne QUESTION/VRAAG 4 4.1.1 Addition/Addisie / Hydrogenation/Hidrogenering  (1) 4.1.2 Substitution/Substitusie (Vervanging) / Halogenation/Halogenering / (1) Chlorination/Chlorogenering   4.2 C2H4 +H H2 → CH 2H6 H (balancing/balansering H ) MarkingC C C C criteria/Nasienkriteria:  One mark for reactants / Een punt vir reaktanse H HH H  One mark for product/ Een punt vir produk (3)  One mark for balancing/ Een punt vir balansering Note/Let wel: One mark for balancing when structural or condensed structural formulae used / Een punt vir balansering indien struktuurformule of gekondenseerde struktuurformule gebruik word. 4.3.1 Combustion/Verbranding  / Oxidation/Oksidasie (1) 4.3.2 Carbon dioxide/Koolstofdioksied  / CO2 Accept/Aanvaar: Carbon(IV)oxide / Koolstof(IV)oksied (2) 4.4.1 Substitution/Substitusie (Vervanging)  / Hydrolysis/Hidrolise (1) 4.4.2 Mild heat/Matige hitte  Diluted strong base/Verdunde sterk basis  OR/OF Excess water/ Oormatige water Accept/Aanvaar: Diluted/Verdunde NaOH / KOH (2) 4.4.3 Ethanol/Etanol  (2) 4.5.1 Semiconductors/Halfgeleiers  / Metalloids/Metalloïde / Semimetals/Halfmetale (1) 4.5.2 The process of adding impurities to intrinsic semiconductors.  Die proses om onsuiwerhede by intrinsieke halfgeleiers te voeg. (2) 4.5.3 Forward bias/Meevoorspanning  (1) [17] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com Technical Sciences/P2/Tegniese Wetenskappe/V2 6 DBE/November 2022 NSC/NSS – Marking Guidelines/Nasienriglyne QUESTION/VRAAG 5 5.1 +2  (1) 5.2 The decomposition of a substance  when electric current is passing through it.  Die ontbinding van 'n stof  wanneer elektriese stroom daardeur beweeg.  OR/OF The chemical process in which electrical energy is converted to chemical energy. Die chemiese proses waar elektriese energie na chemiese energie omgeskakel word. OR/OF The use of electrical energy to produce a chemical change. Die gebruik van elektriese energie om chemiese verandering teweeg te bring. (2) 5.3 Endothermic/Endotermies  (1) 5.4 Q (1) 5.5.1 Bubbles form/Borrels vorm  / Effervescence/Opbruising (1) 5.5.2 Mass increases/Massa neem toe  / Reddish brown deposit (copper) forms / Rooibruin neerslag (koper) vorm  (1) 5.6 Cu2+ (aq) + 2Cℓ-(g)→ Cu(s) + Cℓ2(g)  (balancing/balansering ) H H H H OR/OF C C C C CuCℓ2(aq) → Cu(s) + Cℓ2(g) (balancing/balansering) H H H H Marking criteria/Nasienkriteria:  One mark for reactants / Een punt vir reaktanse  One mark for product/ Een punt vir produk  One mark for balancing/ Een punt vir balansering Note/Let wel: Do NOT penalise when phases are omitted, but penalise when incorrect phases are indicated. / MOENIE penaliseer indien fases uitgelos word nie, maar penaliseer indien verkeerde fases aangedui word. (3) 5.7 In molten CuCℓ2, ions are able to move freely.  In gesmelte CuCℓ2 is ione instaat om vrylik te beweeg.  Accept/Aanvaar: Molten CuCℓ2 will conduct electricity (while a solid will not). Gesmelte CuCℓ2 sal elektrisiteit gelei (terwyl 'n vaste stof dit nie sal doen nie). (2) [12] Copyright reserved/Kopiereg voorbehou Please turn over/Blaai om asseblief

Downloaded from hlayiso.com Technical Sciences/P2/Tegniese Wetenskappe/V2 7 DBE/November 2022 NSC/NSS – Marking Guidelines/Nasienriglyne QUESTION/VRAAG 6 6.1 Phase boundary/Fasegrens  / Interphase/Tussenfase Accept/Aanvaar: phase separator/faseskeier (1) 6.2 Concentration/Konsentrasie: 1 mol.dm-3  Temperature/Temperatuur: 25 oC  / 298 K (2) 6.3 Copper (II) ions/Koper(II)ione  / Cu2+ (2) 6.4.1 Negative/Negatief  (1) 6.4.2 Positive/Positief  (1) 6.5 Eθcell/sel = Eθcathode/katode - Eθanode/anode  Marking criteria/Nasienkriteria:  Accept any other correct formula from 1,10  = 0,34  - Eθ(Y) the data sheet.  Penalise with one mark for using Eθ(Y) = - 0,76 V  unconventional or incomplete formula. Y is Zinc (Zn)/Y is Sink   Aanvaar enige ander korrekte formule vanaf die gegewensblad.  Penaliseer met een punt vir gebruik van OR/OF onkonvensionele of onvolledige formule. Y → Y2+ + 2e-  Eθ(Y) = - 0,76 V  Cu2+ + 2e- → Cu Eθcathode/katode = 0,34 (V)  Eθcell/sel = 1,10 (V)  Y is Zinc (Zn) / Y is sink (Zn)  (5) [12] TOTAL/TOTAAL: 75 Copyright reserved/Kopiereg voorbehou