NATIONAL SENIOR CERTIFICATE/ NASIONALE SENIOR SERTIFIKAAT GRADE/GRAAD 12

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1 NATIONAL SENIOR CERTIFICATE/ NASIONALE SENIOR SERTIFIKAAT GRADE/GRAAD 12 PYSICAL SCIENCES: CEMISTRY (P2) FISIESE WETENSKAPPE: CEMIE (V2) NOVEMBER 2017 MARKING GUIDELINES/NASIENRIGLYNE MARKS/PUNTE: 150 These arking guidelines consist of 11 pages. ierdie nasienriglyne bestaan uit 11 bladsye.

2 Physical Sciences P2/Fisiese Wetenskappe V2 2 DBE/Noveber 2017 QUESTION/VRAAG D (2) 1.2 B (2) 1.3 C (2) 1.4 A (2) 1.5 C (2) 1.6 C (2) 1.7 C (2) 1.8 A (2) 1.9 B (2) 1.10 B (2) [20] QUESTION/VRAAG Esters Ethyl butanoate /Etielbutanoaat (2) Butanoic acid/butanoësuur O C C C C C C O O C C C C C (2) C (3)

3 Physical Sciences P2/Fisiese Wetenskappe V2 3 DBE/Noveber C n 2n ethyl-2,6-diethylhept-3-yne/5-ethyl-2,6-diethyl-3-heptyne 5-etiel-2,6-dietielhept-3-yn/5-etiel-2,6-dietiel-3-heptyn (3) [13] QUESTION/VRAAG ANY ONE/ENIGE EEN: They have ONLY single bonds. ulle het SLEGS enkelbindings. They have single bonds between C atos. ulle het enkelbindings tussen C-atoe. They have no double OR triple bonds OR ultiple bonds. ulle het geen dubbel- OF trippelbindings OF eervoudige bindings nie. They contain the axiu nuber of atos bonded to C atos. ulle bevat die aksiu getal -atoe gebind aan C-atoe. Each C ato is bonded to four other atos. Elke C-atoo is gebind aan vier ander atoe. 3.2 The pressure exerted by a vapour in equilibriu with its liquid in a closed syste. Die druk uitgeoefen deur 'n dap in ewewig et sy vloeistof in 'n geslote sistee. (2) Increases/Verhoog Q It is the teperature where the graph intercepts the dotted line. Dit is die teperatuur waar die grafiek die stippellyn sny. OR/OF It is the teperature where the vapour pressure of copound Q equals atospheric pressure/is equal to 760 g. Dit is die teperatuur waar die dapdruk van verbinding Q gelyk is aan atosferiese druk/gelyk is aan 760 g. (2) S At a given teperature, S has the lowest vapour pressure/highest boiling point. By 'n gegewe teperatuur het S die laagste dapdruk/hoogste kookpunt. Strongest interolecular forces/london forces/dispersion forces/induced dipole forces. Sterkste interolekulêre kragte/london-kragte/dispersiekragte/ geïnduseerde dipoolkragte. ighest energy needed to overcoe/break the interolecular forces. oogste energie benodig o interolekulêre kragte te oorko/breek. (4)

4 Physical Sciences P2/Fisiese Wetenskappe V2 4 DBE/Noveber C C C C C OR/OF C C C C C 2-ethylbutane 2-etielbutaan 2,2-diethylpropane 2,2-dietielpropaan (3) igher than/oër as [14] QUESTION/VRAAG Secondary/Sekondêre The C ato bonded to the O group is bonded to TWO other C atos. Die C-atoo gebind aan die O-groep is aan TWEE ander C-atoe gebind. (2) Dehydration Dehidrasie/dehidratering ydration idrasie/hidratering Dehydrohalogenation/dehydrobroination Dehidrohalogenasie/dehidrohalogenering/dehidrobroinasie/ dehidrobroinering Substitution/ydrolysis Substitusie/idrolise Dilute base/sodiu hydroxide/nao Verdunde basis/natriuhidroksied/nao Moderate teperature/(ild) heat Matige teperatuur/(atige) hitte (2) broobutane /2-broobutaan (2) 4.4 NaO/KO

5 Physical Sciences P2/Fisiese Wetenskappe V2 5 DBE/Noveber C C C C + C C C C (3) 4.6 Butane/Butaan [15] QUESTION/VRAAG ANY ONE/ENIGE EEN: Change in concentration of products/reactants per (unit) tie. Verandering in konsentrasie van produkte/reaktanse per (eenheid) tyd. Rate of change in concentration. Tepo van verandering in konsentrasie. Change in aount/nuber of oles/volue/ass of products or reactants per (unit) tie. Verandering in hoeveelheid/getal ol/volue/assa van produkte of reaktanse per (eenheid) tyd. Aount/nuber of oles/volue/ass of products fored or reactants used per (unit) tie. oeveelheid/getal ol/volue/assa van produkte gevor of reaktanse gebruik per (eenheid) tyd. (2) 5.2 Marking criteria/nasienriglyne: Dependent and independent variables correctly identified. Afhanklike en onafhanklike veranderlikes korrek geïdentifiseer. Ask a question about the relationship between the independent and dependent variables./vra 'n vraag oor die verwantskap tussen die afhanklike en onafhanklike veranderlikes. Exaples/Voorbeelde: What is the relationship between concentration and reaction rate? Wat is die verwantskap tussen konsentrasie en reaksietepo? ow does the reaction rate change when the concentration changes/increases/decreases? oe sal die reaksietepo verander wanneer die konsentrasie verander/ verhoog/verlaag? (2) 5.3 Q Saller gradient./less steep. Kleiner gradiënt./minder steil. Reaction I has the lowest Cl concentration and will take longer to reach copletion/for the axiu volue of gas to be fored. Reaksie I het die laagste Cl-konsentrasie en nee langer o voltooi te word/die aksiu volue gas te vor. (3)

6 Physical Sciences P2/Fisiese Wetenskappe V2 6 DBE/Noveber OPTION 1/OPSIE 1 V Ave rate/ge. tepo = t V 15 = 30 0 V( 2 ) produced/berei = 450 c 3 V n( 2 ) produced/berei = V 450 = = 0,0188 ol n(zn) = n( 2 ) = 0,0188 ol n(zn) used/gebruik = M 0,0188 = 65 (Zn) = 1,22 g 15 Ave rate/ge. tepo = = 6, ol s -1 V( 2 ) produced/berei = 6,25 30 = 0,0188 ol n(zn) = n( 2 ) = 0,0188 ol n(zn) used = M 0,0188 = 65 (Zn) = 1,22 g OPTION 3/OPSIE 3 V Ave rate/ge. tepo = t V 15 = 30 0 V( 2 ) produced/berei = 450 c 3 65 g Zn c 3 x g Zn 450 c 3 x = 1,22 g (5) Equal to/gelyk aan Equal to/gelyk aan 5.6 At higher teperature the average kinetic energy of particles is higher. By hoër teperatuur is die geiddelde kinetiese energie van deeltjies hoër. More olecules gain sufficient/enough kinetic energy OR ore olecules have kinetic energy equal to or greater than the activation energy. Meer olekule het voldoende/genoeg kinetiese energie OF eer olekule het kinetiese energie gelyk aan of groter as die aktiveringsenergie. More effective collisions per unit tie./frequency of effective collisions increases. Meer effektiewe botsings per eenheidtyd./frekwensie van effektiewe botsings nee toe. (3) [17]

7 Physical Sciences P2/Fisiese Wetenskappe V2 7 DBE/Noveber 2017 QUESTION/VRAAG The stage in a cheical reaction when the rate of forward reaction equals the rate of reverse reaction. Die stadiu in 'n cheiese reaksie wanneer die tepo van die voorwaartse reaksie gelyk is aan die tepo van die terugwaartse reaksie. OR/OF The stage in a cheical reaction when the concentrations of reactants and products reain constant. Die stadiu in 'n cheiese reaksie wanneer die konsentrasies van reaktanse en produkte konstant bly. (2) OPTION 1/OPSIE 1 n = M 1,12 = 28 = 0,04 ol Initial quantity (ol) Aanvangshoeveelheid (ol) Change (ol) Verandering (ol) Quantity at equilibriu (ol)/ oeveelheid by ewewig (ol) Equilibriu concentration/ Ewewigskonsentrasie (ol d -3 ) [CO][Br ] K = 2 c [COBr ] 2 2 (0,02) 0,19 = [COBr2 ] [COBr 2 ] = 2,11 x 10-3 ol d -3 COBr 2 CO Br ,04 0,04 0,04 0,04 0,04 0,02 0,02 Divide by 2 Deel deur 2

8 Physical Sciences P2/Fisiese Wetenskappe V2 8 DBE/Noveber 2017 n = M 1, 2 = 28 = 0,04 ol n(co) fored/gevor = n(br 2 ) fored/gevor = 0,04 ol c(co) eq/ewe = c(br 2 ) eq/ewe = V n 0,04 = 2 = 0,02 ol d -3 [CO][Br ] K = 2 c [COBr2 ] 2 (0,2) 0,19 = [COBr2 ] [COBr 2 ] = 2,11 x 10-3 ol d -3 (7) OPTION 1/OPSIE 1 n(cobr 2 ) eq/ewewig = cv = 2, = 4, ol n(cobr 2 ) initial/begin = 0,04 + 4, = 0,044 ol 0,04 % decoposed = 100 0,044 = 90,46% Range/Gebied: 90,46 90,9% n(cobr 2 ) eq/ewewig = cv = 2, = 4, ol n(cobr 2 ) initial/begin = 0,04 + 4,22 x 10-3 = 0,044 ol (COBr 2 ) initial/begin = nm = 0, = 8,27 g (COBr 2 ) reacted/reageer = 0, = 7,52 g 7,52 % decoposed/ontbind = 100 8,27 = 90,9% (4) 6.3 K c < 0, Decreases/Verinder A decreases in pressure favours the reaction that produces the larger nuber of oles of gas./'n Afnae in druk bevoordeel die reaksie wat die groter aantal ol gas lewer. The forward reaction will be favoured./die voorwaartse reaksie sal bevoordeel word. (3) [17]

9 Physical Sciences P2/Fisiese Wetenskappe V2 9 DBE/Noveber 2017 QUESTION/VRAAG Weak/Swak Dissociates/Ionises incopletely (in water) Dissosieer/Ioniseer onvolledig (in water) (2) N O/water OR/OF N Acidic/Suur p < 7 (2) OPTION 1/OPSIE 1 p = -log[ 3 O + ] 6 = -log[ 3 O + ] [ 3 O + ] = ol d -3 [ 3 O + ][O - ] = [O - ] = ol d OPTION 1/OPSIE 1 n(na2 CO3 ) = M 0,29 = 106 = 2, ol n(cl) = 2n(Na 2 CO 3 ) = 5, ol p + po = po = 14 po = -log[o - ] 8 = -log[o - ] [O - ] = ol d -3 (4) n(na2 CO3 ) = M 0,29 = 106 = 2, ol n(cl) = 2n(Na 2 CO 3 ) = 5, ol c(cl) dilute/verdun = V n 3 5,47x10 = 0,05 = 0,1094 ol d -3 cv(cl) dilute/verdun = cv(cl) conc/gekons 0, = (Cl) conc/gekons 5 c(cl) conc/gekons = 10,94 ol d -3 In 50 c 3 : n(cl) = 5, ol In 500 c 3 : 500 n(cl) = (5, ) 50 = 0,547 ol 1000 c(cl) conc/gekons = 0,547 5 = 10,94 ol d -3 (7) [17] QUESTION/VRAAG Volteter/Multieter Anode

10 Physical Sciences P2/Fisiese Wetenskappe V2 10 DBE/Noveber Ag + (aq) + Al(s) 3Ag(s) + Al 3+ (aq) Bal. (3) OPTION1/OPSIE 1 θ θ θ E cell = Ereduction Eoxidation = +0,80 - (- 1,66) = 2,46 V Ag + (aq) + e - Ag(s) 0,80 V Al(s) Al 3+ (aq) + 3e - 1,66 V 3Ag + (aq) + Al(s) 3Ag(s) + Al 3+ (aq) 2,46 V (4) Platinu/Pt/Carbon/C/Koolstof ANY TWO/ENIGE TWEE: Concentration/Konsentrasie: 1 ol d -3 Teperature/Teperatuur: 25 C/298 K Pressure/Druk: 101,3 kpa/1,01 x 10 5 Pa/1 at (2) Zinc/Zn/sink PQ [14] QUESTION/VRAAG DC 9.2 Cathode/Katode Cu 2+ (aq) + 2e - Cu 9.3 Cu 2+ is a stronger oxidising agent than Zn 2+ ions and therefore Zn 2+ ions will not be reduced (to Zn). Cu 2+ is 'n sterker oksideeriddel as Zn 2+ -ione en dus sal Zn 2+ -ione nie gereduseer word nie (na Zn). (3) (Chlorine) gas/bubbles is/are fored. (Chloor)gas/borrels vor Decreases/Verlaag [9]

11 Physical Sciences P2/Fisiese Wetenskappe V2 11 DBE/Noveber 2017 QUESTION 10/VRAAG Aonia/Aoniak NO Catalytic oxidation of aonia Katalitiese oksidasie van aoniak Platinu/Pt Ostwald (process)/ostwald(proses) aber (process)/aber(proses) N 3 + NO 3 N 4 NO 3 Bal. (3) OPTION 1/OPSIE 1 N : P : K 10 : 5 : (fertiliser/kunsis) = x (fertiliser/kunsis) = x = 0,75 kg (P) = 30 5 x 4,5 = 4,5 kg = 0,75 kg (2) %fertiliser/kunsis = = 30% %filler/bindstof = = 70% 70 (filler/bindstof) = x = 10,5 kg (3) [14] TOTAL/TOTAAL: 150

NATIONAL SENIOR CERTIFICATE/ NASIONALE SENIOR SERTIFIKAAT GRADE/GRAAD 10

NATIONAL SENIOR CERTIFICATE/ NASIONALE SENIOR SERTIFIKAAT GRADE/GRAAD 10 PHYSICAL SCIENCES: CHEMISTRY (P2) FISIESE WETENSKAPPE: CHEMIE (V2) NOVEMBER 2017 MARKING GUIDELINES/NASIENRIGLYNE MARKS/PUNTE: 150