Technical Sciences Grade 12 P2 Gauteng Mock 2019 Memo (Afr)

Downloaded from hlayiso.com PREPARATORY EXAMINATION VOORBEREIDENDE EKSAMEN 2019 MARKING GUIDELINES / NASIENRIGLYNE TECHNICAL SCIENCES/ TEGNIESE WETENSKAPPE (PAPER / VRAESTEL 2) 11102 12 pages / bladsye . 1

Downloaded from hlayiso.com 11102 / 19 GAUTENG DEPARTMENT OF EDUCATION / GAUTENGSE DEPARTEMENT VAN ONDERWYS PREPARATORY EXAMINATION / VOORBEREIDENDE EKSAMEN TECHNICAL SCIENCES / TEGNIESE WETENSKAPPE (Paper / Vraestel 2) MARKING GUIDELINES / NASIENRIGLYNE QUESTION / VRAAG 1 1.1 D  (2) 1.2 C  (2) 1.3 A  (2) 1.4 D  (2) 1.5 A  (2) 1.6 B  (2) 1.7 C  (2) 1.8 C  (2) 1.9 D  (2) 1.10 D  (2) [20] QUESTION / VRAAG 2 2.1 A series of compounds that can be described by the general formulae in which they differ – CH2 group.  / ʼn Reeks organiese verbindings wat deur dieselfde algemene formule beskryf kan word en waarin die een lid van die volgende verskil met CH2-groep. (2) 2.2.1 Alkene / Alkeen (1) 2.2.2 Ester (1) 2.2.3 Alkane / Alkaan  (1) 2.3.1 Hydroxyl group / Hidroksielgroep (1) 2.3.2 Carboxyl group/ Karboksielgroep (1) 2

Downloaded from hlayiso.com 11102 / 19 2.4 2.4.1 1-chloropropane / If hyphen is omitted (1/2) / 1-chloropropaan Koppelteken uitgelaat (1/2) (2) 2.4.2 Butan-2-ol / If hyphen is omitted (1/2) / Butan-2-o1 Koppelteken uitgelaat (1/2) (2) 2.4.3 2-methylprop-1-ene/ If hyphen is omitted (1/2) / 2-metielprop-1-een Koppelteken uitgelaat (1/2) (2) 2.5 B,C,F and H (4) 2.6 D and G / D en G B and H / B en H (2) 2.7 H H H H C C C  H H H H C H  H Marking criterian / Nasienriglyne  Whole structure correct/ Hele struktuur korrek  Methyl on second carbon/ Metiel op 2de C (2) 2.8  (2) [23] 3

Downloaded from hlayiso.com 11102 / 19 QUESTION / VRAAG 3 3.1 The temperature at which the vapour pressure is equal to the atmospheric pressure / Die temperatuur waar die dampdruk gelyk is aan die atmosferiese druk. (2) 3.2.1 Hexane / Heksaan (1) 3.2.2  Hexane has a larger molecular mass/number of carbons than butane.  / Heksaan het ʼn groter molekulêre massa / aantal C- atome as butaan.  The intermolecular forces/london forces/ion dipole forces between molecules of hexane are stronger that those between molecules of butane.  / Intermolekulêre kragte / london / ioon dipool kragte tussen molekule van heksaan is groter as tussen molekule van butaan.  More energy is required to overcome intermolecular forces of hexane than those of butane.  / Meer energie is nodig om intermolekulêre kragte van heksaan te oorkom, minder energie nodig om IM kragte van butaan te oorkom OR / OF  Butane has a lower molecular mass/number of carbons than hexane.  / Butaan het kleiner molekulêre massa/getal C-atome as heksaan.  The intermolecular forces/london forces/ion dipole forces between molecules of butane are weaker that those between molecules of hexane. / Die IM kragte/london/ioondipool kragte tussen molekule van butaan is swakker as tussen molekule van heksaan.  Less energy is required to overcome intermolecular forces of butane than those of hexane.  / Minder energie nodig om IM van butaan te oorkom as die van heksaan. (3) 3.2.3 Methane  / Metaan (1) 3.2.4  The boiling point of methane is lower than that of pentane.  / Die kookpunt van metaan is laer/minder as diè van pentaan.  The lower the boiling point, the more the vapour pressure.  / Hoe laer / kleiner die kookpunt, hoe meer die dampdruk. (2) [9] 4

Downloaded from hlayiso.com 11102 / 19 QUESTION / VRAAG 4 4.1 Saturated hydrocarbons have single bonds only.  / Versadigde koolwaterstowwe het slegs enkele bindings. Unsaturated hydrocarbons have double or triple bonds. / Onversadigde koolwaterstowwe het dubbel of drievoudige bindings. (2) 4.2.1 Reaction 1 – hydrohalogenation  (accept: addition) / Reaksie 1 – hidrohalogenering (aanvaar addisie) (1) 4.2.2 Reaction 2 – hydrolysis  (accept: substitution) / Reaksie 2 – hidroliese (aanvaar substitusie) (1) 4.2.3 Reaction 3 – hydration  (accept addition) / Reaksie 3 – hidrasie (aanvaar addisie) (1) 4.3.1 Low / mild temperatures  / Lae / matige temperature OR / OF A dilute solution of a strong base (e.g. NaOH). (Any ONE / Enige EEN) / Verdunde oplossing van ʼn sterk basis van NaOH (1) 4.3.2 Water must be present in excess.  / Water in oormaat An acid catalyst (H3PO4) is needed for this reaction to take place.  / ʼn Suur katalis (H3PO4) is nodig vir die reaksie om plaas te vind. (2) 4.4 2 C4H10 + 13O2 → 8CO2 + 10H2O (bal)  Marking criterian / Nasienriglyne  Reactants / Reaktante  Products / Produkte  Balancing / Balansering (3) 4.5 Ethene  / Eteen (1) 4.6 Making plastic products such as / Maak plastiek produkte soos Film/ Film (bv. “glad wrap”, plastiek sake, voering in karton houers Injection moulding/ Spuitgiet (bv. bakke, emmers, kratte, asblikke) Blow moulding / Blaasvorming (bv. spuitbottels) Extrusion / Extrusie (bv. buigbare waterpype, kabel omhulsels) (Accept any TWO applicable uses.) / (Aanvaar enige TWEE toepaslike gebruike.) (2) [14] 5

Downloaded from hlayiso.com 11102 / 19 QUESTION / VRAAG 5 5.1 Splitting up (decomposition) of a compound using electrical current.  / Opbreek van ʼn chemiese stof d.m.v. elektriese stroom OR / OF The chemical process where electrical energy is transformed into chemical energy / Die chemiese proses waar elektriese energie omgeskakel word in chemiese energie (2) 5.2 Electrical energy is converted into chemical energy. / Elektriese energie word omgeskakel in chemiese energie. (2) 5.3 B (1) 5.4 Chlorine gas,  Cℓ2 / Chloorgas, Cℓ2 (2) 5.5 Cations-Cu2+  / Katione-Cu2+ Anions-Cℓ -  / Anione-Cℓ - (2) 5.6 Copper /Cu deposit  / Koperneerslag/ Cu-neerslag (1) 5.7.1  Less pollution because of less CO2 exhaust fumes   Lower CO2 emission reduces the effect of global warming.   Effective recycling of waste products such as used fats and oils. (Any TWO) • Minder besoedeling a.g.v. CO2 uitlaatgasse. • Minder CO2 gasse verminder die effek van aardverwarming. • Effektiewe herwinning van afvalprodukte soos gebruikte vette en olies. (Enige TWEE) (2) 5.7.2  Solar energy /photovoltaic cells / Sonenergie / Fotorottaïese selle  biodiesel  Wind energy / Wind energie  Hydroelectricity / Hidroelektrisiteit (Any TWO) / (Enige TWEE) (2) [14] 6

Downloaded from hlayiso.com 11102 / 19 QUESTION / VRAAG 6 6.1 An electrochemical cell where chemical energy is converted into electrical energy  / Elektrochemiese sel waar chemiese energie omgeskakel word in elektriese energie (2) 6.2.1 Copper (electrode)  / Koper (elektrode) (1) 6.2.2 Zinc sulphate (ZnSO4)/zinc nitrate (ZnNO3)  / Sinksulfaat (ZnSO4) / Sinknitraat (ZnNO3) (Accept any Zn electrolyte that does not form a precipitate. / Aanvaar enige Zn elektroliet wat nie ʼn neerslag vorm nie.) (1) 6.2.3 Salt bridge  /Soutbrug (1) 6.2.4 0V (1) 6.2.5 The cell is incomplete.  / Sel is onvolledig OR / OF No ions are moving in the circuit. / Geen ione kan in die stroombaan beweeg nie. (2) 6.2.6 KNO3 / KC (1) 6.2.7 From E to D / Van E na D (1) 6.3 Zn(s)  → Zn2+ (aq) + 2e Marking criterian / Nasienriglyne  Reactants / Reaktante  Products  / Produkte  Balancing / Balansering (2) 6.4 Temperature = 298K/25 ºC  / Temperatuur = 298K/25 ºC Concentration = 1mol.dm-3  / Konsentrasie = 1mol.dm-3 (2) 6.5.1 Zinc / Zn electrode / Sink/ Zn-elektrode (1) 6.5.2 Zn (s) / Zn2+ (aq)  (1 mol.dm-3) //  Cu2+ (aq) / (1 mol.dm-3) Cu (s)  All phases correct / Alle fases korrek. (4) 6.5.3 E°cell = E°cathode – E°anode / E° sel = E° katode / E° anode = 0,34 – (-0,76)  = 1,1 V (4) 6.6 The solution will turn colourless. / Die oplossing word kleurloos. (1) [24] 7

Downloaded from hlayiso.com 11102 / 19 QUESTION / VRAAG 7 7.1 Refraction: The bending of light when it passes from one medium to another.  / Refraksie: Lig verander van rigting wanneer dit van een medium na ʼn ander medium beweeg. (2) 7.2 Incident ray / Invalstraal Refracted ray / Gebreekte straal Emergent ray / Uittredende straal (2) 7.3.1 Critical angle: The angle of incidence in the denser medium such that the refracted ray just passes through the surface of separation of the two media.  / Grenshoek: die invalshoek in die digter medium sodat die gebreekte straal net deur die oppervlak wat die twee media skei, gaan. (2) 8

Downloaded from hlayiso.com 11102 / 19 7.3.2 Incident ray / Reflected ray / Weerskaatse straal Invallende straal Totale internal reflection / Totale interne weerkaatsing Marking criterion / Nasien kriteria Marks / Punte Correct direction and label of incident ray / 1 Korrekte rigting en byskrif vir invallende straal Correct direction and label of reflected ray inside the glass slab / Korrekte rigting en byskrif vir 1 weerkaatste straal binne die glasblok Correct magnitude of incident angle / 1 Hoekgrootte invalshoek Correct magnitude of reflected angle inside the glass slab / Korrekte grootte van 1 weerkaatsingshoek binne die glasblok (4) 7.3.3 Total internal reflection  / Totale interne weerkaatsing (1) 7.3.4 Total internal reflection: When the angle of incidence is greater than the critical angle,  the ray of light reflects into the original medium.  / Totale interne weerkaatsing: Wanneer die invalshoek groter is as die grenshoek, word die ligstraal terug weerkaats in die oorspronklike medium. (2) 7.3.5 Refractometers / Refraktometer Prisms in binoculars / Prismas in verkykers Optical finger printing devices / Optiese vingerafdruk toestel In fluorescence microscopes / Fluoressensie mikroskoop Gonioscopy / Gonioskopie (meet vloeistof druk in die oog) X-ray mirrors / X-staal weerspieëling Galt analysis instruments / Galt analiese instrumente Optical fibres in communication / Optiese vessel in kommunikasie Automotive rain sensors / Outomatiese reënsensor (Any ONE) / (Enige EEN) (1) 7.3.6 The light is in the denser medium and approaching the less dense medium.  / Lig beweeg van opties digter medium na opties minder digte medium. The angle of incidence is greater than the critical angle.  / Invalshoek is groter as die grenshoek (2) [16] 9

Downloaded from hlayiso.com 11102 / 19 QUESTION 8 / VRAAG 8 8.1 Convex lens  / Konvekslens (1) 8.2 Object / Voorwerp Image / Beeld √ Marking criterian / Nasienriglyne Marks / Punte Ray parallel to the principal axis / Straal parallel aan hoofas 1 Ray passing straight through the optical centre / Straal deur 1 optiese middelpunt Image formed between F and 2F on the other side of the lens / 1 Beeld gevorm tussen F en 2F aan die ander kant van die lens Image is small and inverted / Beeld is kleiner en omgekeerd 1 (4) 8.3 Diminished / small  / Verklein Inverted  / Omgekeerd (2) Object / Image / Voorwerp Beeld 10

Downloaded from hlayiso.com 11102 / 19 8.4.1 Marking criterian / Nasienriglyne Marks / Punte Ray from the top of the object parallel to the principal axis / 1 Straal vanaf die bopunt van die voorwerp, parallel aan hoofas Ray from the top of the object passing straight through the optical centre / Straal vanaf bopunt van voorwerp, reguit deur 1 optiese middelpunt Image formed at a point where a ray seeming to come from F meets the one passing the optical centre and diverging / Beeld 1 gevorm by ‘n punt waar dit lyk of die straal vanaf F kom en kruis die straal deur die optiese middelpunt Diverging ray from the centre of the lens extrapolated from F / Divergerende straal vanaf die middelpunt van die lens, terug 1 verleng deur F (4) 8.4.2 Small / diminished / Klein / Verklein Upright / Regop (2) 8.4.3 Far-sightedness / long-sightedness / hypermetropia / Versiendheid / hipermetropie (1) [14] 11

Downloaded from hlayiso.com 11102 / 19 QUESTION 9 / VRAAG 9 9.1 Self-propagating, changing magnetic and electric fields that are mutually perpendicular to each other and to the direction of propagation/ Verandering van magnetiese en elektriese velde loodreg op mekaar en die rigting van die voortplanting van die golf. (2) 9.2 Gamma rays, X-rays,  ultraviolet trays, infrared rays / microwaves, radio waves.  Gamma, X-straal, UV, infrarooi mikrogolwe, radiogolwe Marking criterian / Nasienriglyne 1 mark for 2 types of electromagnetic waves that follow each other in order of increasing wavelength / 1 punt vir 2 tipes elektromagnetiese golwe in volgorde (3) 9.3.1 X-rays / X-strale (1) 9.3.2 Gamma rays / Gammastrale (1) 9.4 Ultraviolet rays cause the body to produce vitamin D, and this is used by doctors to treat vitamin D deficiency and some skin disorders. / Ultravioletstrale help liggaam om Vit. D te produseer wat gebruik word om vit. D-tekorte aan te vul en sekere velkwale te verbeter. (1) 9.5 𝑐 = 𝑓𝜆 3 x 108  = 1,0 x 1010 x 𝜆 = 3 x 10-2m.  (4) 9.6 𝐸 = ℎ𝑓 = ℎ𝜆𝑐   ( 6,63)(3 × 108 )(10−34 ) =  600 × 10−9 = 3,32 x 10-35 J (4) [16] TOTAL / TOTAAL: 150 12