NATIONAL SENIOR CERTIFICATE/ NASIONALE SENIOR SERTIFIKAAT

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NOVEMBER 2017 MARKING GUIDELINES/NASIENRIGLYNE MARKS/PUNTE: 150 These

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

2 Physical Sciences P2/Fisiese Wetenskappe V2 2 DBE/Noveber 2017 QUESTION/VRAAG C (2) 1.2 A (2) 1.3 C (2) 1.4 A (2) 1.5 C (2) 1.6 D (2) 1.7 A (2) 1.8 D (2) 1.9 B (2) 1.10 C (2) [20]

3 Physical Sciences P2/Fisiese Wetenskappe V2 3 DBE/Noveber 2017 QUESTION/VRAAG A covalent bond is the sharing of electrons between two atos to for a olecule. 'n Kovalente binding is die deel van elektrone tussen twee atoe van 'n olekuul. (2) H H H C Cl (2) O C O (2) 2.3 None/zero /Geen/nul (1) 2.4 H 2 O (1) H 2 O is angular/bent/hoekig (1) CO 2 is linear/lineêr (1) 2.6 (The charge distribution in) CH 3 Cl is asyetrical and CH 4 is syetrical. (Die verspreiding van lading in) CH 3 Cl is asietries en CH 4 is sietries. The chlorine has a higher electronegativity than the hydrogen. Die chloor het 'n hoër elektronegatiwiteit as waterstof. (1) [11] QUESTION/VRAAG Both water and ethanol have hydrogen bonds Beide water en etanol het waterstofbindings which are the sae in relative strength. wat dieselfde relatiewe sterkte is. Substances with coparable relative strength in interolecular forces will dissolve. Stowwe wat vergelykbare relatiewe sterkte in interolekulêre kragte het, sal in ekaar oplos (3) 3.2 The interolecular forces between the olecules of iodine and broine are both London forces (Van der Waals forces/induced dipole forces). Die interolekulêre kragte tussen olekules van jodiu en broo is beide London kragte (van der Waalskragte/geïnduseerde kragte). (3)

4 Physical Sciences P2/Fisiese Wetenskappe V2 4 DBE/Noveber 2017 Iodine olecules have a bigger olecular ass than the olecules of broine/iodine olecules have a larger surface area than olecules of broine/iodine olecules have ore electrons than that of broine and thus have a larger polarity (any option) Jodiuolekules het 'n groter olekulêre assa as die olekules van broo/jodiuolekules het 'n groter oppervlak as brooolekules/ jodiuolekules het eer elektrone as die van broo en het daaro 'n groter polariteit (enige opsie) The bigger the olecules/larger the surface are of the olecules, the stronger the interolecular forces. Hoe groter die olekule/oppervlakte van die olekule, hoe sterker is die interolekulêre kragte. 3.3 The interolecular forces between phosphine olecules are dipoledipole forces/van der Waals forces. Die interolekulêre kragte tussen fosfien se olekules is dipooldipoolkragte/van der Waalskragte The interolecular forces between aonia olecules are hydrogen bonds. Die interolekulêre kragte tussen die olekules van aoniak is waterstofbindings The dipole-dipole forces are weaker than the hydrogen bonds. Die dipool-dipoolkragte is swakker as die waterstofbindings Weaker forces will cause the olecules to evaporate faster/stronger forces will evaporate slower Swakker kragte sal veroorsaak dat olekules vinniger verdap/sterker kragte sal veroorsaak dat olekules stadiger verdap (4) 3.4 Broine /Broo (1) 3.5 NEGATIVE MARKING FROM 3.4/NEGATIEWE NASIEN VANAF 3.4 The boiling point of broine is lower than the other two liquids therefore it has weaker interolecular forces. Die kookpunt van broo is laer as die ander twee vloeistowwe en het daaro swakker interolekulêre kragte. If the interolecular forces are weaker, the vapour pressure will be higher. Indien die interolekulêre kragte swakker is, sal die dapdruk van die vloeistof hoër wees. The boiling point of water and ethanol are higher than broine, therefore it has stronger interolecular forces. Die kookpunt van water en etanol is hoër as broo en het daaro sterker interolekulêre kragte. If the interolecular forces are stronger, the vapour pressure will be lower. Indien die interolekulêre kragte sterker is, sal die dapdruk laer wees. (2) [13]

5 Physical Sciences P2/Fisiese Wetenskappe V2 5 DBE/Noveber 2017 QUESTION/VRAAG Graph of pressure versus teperature Grafiek van druk teenoor teperatuur 250 Pressure/Druk (kpa) Teperature/Teperatuur (K) Refer to the last page of the arking guidelies for the graph drawn to scale. Verwys na die laaste bladsy van die nasienriglyne vir die skaalgrafiek. Criteria for arking the graph Use of correct scale on both axis Korrekte skaal op die asse At least three (3) points plotted correctly Ten inste drie (3) punte korrek gestip Line of best fit drawn Beste passing lyn getrek Graph drawn to the origin Grafiek getrek deur die oorsprong (4) 4.2 Pressure of an enclosed gas is directly proportional to the teperature if the volue stays constant. Druk van 'n ingeslote gas is direk eweredig aan die teperatuur indien die volue konstant bly. As the pressure of an enclosed gas increases, the teperature increases proportionately. Indien die druk van 'n ingeslote gas verhoog, sal die teperatuur eweredig verhoog (2)

6 Physical Sciences P2/Fisiese Wetenskappe V2 6 DBE/Noveber At very low teperature values, the gas will liquify, not acting like a gas anyore. Teen baie lae tepertuurwaardes sal die gas vervloei en nie soos 'n gas optree nie. (2) 4.4 If the teperature increases, the average kinetic energy of the particles increases. Indien die teperatuur verhoog, nee die geiddelde kinetiese energie van die deeltjies toe The particles ove faster. Die deeltjies beweeg vinniger. The nuber of collisions between the particles increase (and force per unit area). Die aantal botsings tussen die deeltjies nee toe (en die krag per eenheid oppervlak nee toe) If the nuber of collisions increases, the pressure increases. Indien die aantal botsings toenee sal die druk toenee. (4) 4.5 High teperature /Hoë teperatuur Low pressure /Lae druk (2) 4.6 Accept any cobination of coordinates fro the graph for exaple:/ Aanvaar enige kobinasie van koördinate vanaf die grafiek byvoorbeeld: 280,5 155,8 Gradient = = 0,62 280,5 0 Gradient = = 0,62 249,3 0 Gradient = = 0,62 218,1 0 Gradient = = 0,62 (3)

7 Physical Sciences P2/Fisiese Wetenskappe V2 7 DBE/Noveber POSITIVE MARKING FROM 4.6/POSITIEWE NASIEN VANAF 4.6 n = M 48 n = 32 n = 1,5 ole/ol Fro/Vanaf pv = nrt nr Gradient = V (NOTE: Pressure is in kpa on graph to use equation it should be in Pa) (LET WEL: Druk vanaf die grafiek is in kpa en oet eers ogeskakel word na Pa o die forule te gebruik) 1,5(8,31) 620 = V V = 0, 02 3 (20,1 d 3 ) (5) [22] QUESTION/VRAAG p V p V = T1 T (12,6) (36,3) = 298 T 2 T 2 = 226 K T 2 = - 47 C (4) 5.2 pv = nrt ( )(12,6) = n(8,31)(298) n = 534,25 ole/ol (4) [8]

8 Physical Sciences P2/Fisiese Wetenskappe V2 8 DBE/Noveber 2017 QUESTION/VRAAG H 2 O 2 (aq) 2H 2O (l) + O 2 (g) (2) The catalyst lowers the activation energy of the reaction 'n Katalisator verlaag die aktiveringsenergie van die reaksie. (2) OPTION 1/OPSIE 1 V n = V 0,6 n = 24,45 n = 0,0245 ole/ol O 2 produced/gevor H 2 O 2 : O 2 2 : 1 OPTION 2/OPSIE 2 Fro the balanced equation: Vanaf gebalanseerde vergelyking: 68g H 2 O 2 24,45 d 3 O 2 X g H 2 O x 10-3 d ,6 X = 24,45 X = 1,67 g n = 0,049 ole/ol H 2 O 2 reacted/reageer n = M 0,049 = 34 = 1,67 g (6) Magnesiu, the ass of agnesiu after 3 inutes/at the end of the reaction was zero Magnesiu, die assa agnesiu na 3 inute/aan die einde van die reaksie was nul (2) n c = V n 0,36 = 0,5 n = 0,18 ole/olhcl used/gebruik n = M 1,2 n = 24 n = 0,05 ole/ol Mg reacted/reageer Mg : HCl 1 : 2 0,1 ole/ol HCl reacted/reageer Moles of HCl left in the test tube = 0,18 0,1 = 0,08 ole /Mol HCl ongereageer in die proefbuis = 0,18 0,1 = 0,08 ol (7) [19]

9 Physical Sciences P2/Fisiese Wetenskappe V2 9 DBE/Noveber 2017 QUESTION/VRAAG The iniu energy needed for a reaction to take place. Die iniu energie benodig vir die reaksie o plaas te vind. (2) 7.2 An exotheric reaction releases energy OR H < 0 'n Eksoteriese reaksie stel energie vry OF H < 0 (2) 7.3 Potential energy Potensiële energie E a reactants reaktante H products produkte Tie/tyd MARKING CRITERIA/NASIENKRITERIA Activation energy E a correct position and labelled Aktiveringsenergie E a korrekte posisie en benoe Heat of reaction H correct position and labelled Reaksiewarte H korrekte posisie en benoe Products have lower energy than reactants Produkte het laer energie as reaktanse (3) ,76 C : = 6, ,24 H : = 17, 24 1 Divide by the sallest answer Deel deur die kleinste antwoord 6,896 6,896 1 : 2,5 17,24 6,896 2 : 5 C 2 H 5 (4) [11]

10 Physical Sciences P2/Fisiese Wetenskappe V2 10 DBE/Noveber 2017 QUESTION/VRAAG A base is proton acceptor 'n Basis is 'n protonontvanger (2) H 2 SO 4 (aq) + 2NaOH (aq) Na 2 SO 4 (aq) + 2H 2 O (l) balance/balans (3) Sodiu sulphate /Natriusulfaat (2) HSO 4 (2) HSO 4 and/en H 2 SO 4 + H 2 O and/en H 3 O (4) OPTION 1/OPSIE 1 c = MV 6 c = (40)(0,5) c = 0,3 ol.d -3 OPTION 2/OPSIE 2 n = M 6 n = 40 n = 0,15 ole / ol n c = V 0,15 c = 0,5 c = 0,3 ol.d -3 (4) n = M 6 n = 40 n = 0,15 ole/ol NaOH NaOH : NH 4 Cl 1 : 1 n = M 0,15 = 53,5 = 8,025 g NH 4 Cl 8, = 80,25 % pure/suiwer ,25 = 19,75 % ipurities/onsuiwerhede 10 8,025 = 1,975 1, = 19,75% ipurities/onsuiwerhede 10 (6) [23]

11 Physical Sciences P2/Fisiese Wetenskappe V2 11 DBE/Noveber 2017 QUESTION/VRAAG Cr 6+ (+6) (2) 9.2 Gain of electrons Opnee van elektrone (1) 9.3 Fe 2+, the oxidation nuber increases fro +2 to +3 Fe 2+, die oksidasiegetal nee toe van +2 na +3 (2) 9.4 Cr 6+ /Cr 2 O 7 2- (2) 9.5 Cr 2 O H + + 6e - 2Cr H 2 O (1) 9.6 6Fe 2+ 6Fe e - Cr 2 O H + + 6e - 2Cr H 2 O Cr 2 O H + + 6Fe 2+ 2Cr H 2 O + 6Fe 3+ (3) [13] QUESTION/VRAAG Miners do not have to risk their lives going deep or being trapped underground. Mynwerkers het nie 'n lewensgevaarlike risiko o ondergronds vas te val nie. No risk of sink holes Daar ontstaan nie sinkgate nie Any other relevant answer/enige ander relevante antwoord (2) 10.2 Reduction, oxidation nuber of iron decreases fro 6+ to 0. / Reduksie, die oksidasiegetal van yster nee af van 6+ na 0. (2) 10.3 Carbon is a non-renewable recource Koolstof is 'n nie-hernubare bron Carbon dioxide as product can increase global waring Koolstofdioksied as produk kan aardverwaring vererger Any other relevant answer/enige ander relevante antwoord (2) 10.4 The gold does not oxidize easily like iron. /Die goud oksideer nie so aklik soos yster nie. (2) 10.5 It acts as oxidising agent. /Dit tree op as oksideeriddel. (2) [10] TOTAL/TOTAAL: 150

Physical Sciences P2/Fisiese Wetenskappe V2 ANSWER SHEET/ANTWOORDBLAD 12 DBE/Noveber 2017 Hand in this ANSWER SHEET with the ANSWER BOOK./Lewer hierdie ANTWOORDBLAD saa et die ANTWOORDEBOEK in.

12 Physical Sciences P2/Fisiese Wetenskappe V2 ANSWER SHEET/ANTWOORDBLAD 12 DBE/Noveber 2017 Hand in this ANSWER SHEET with the ANSWER BOOK./Lewer hierdie ANTWOORDBLAD saa et die ANTWOORDEBOEK in. NAME/NAAM: Pressure/Druk (kpa) QUESTION/VRAAG 4.1 CLASS/KLAS: GRAPH OF PRESSURE VERSUS TEMPERATURE/GRAFIEK VAN DRUK TEENOOR TEMPERATUUR Teperature/Teperatuur(K)

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