Physical Sciences Grade 12 P2 Eastern Cape Mock 2015 Memo

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE/GRAAD 12 SEPTEMBER 2015 PHYSICAL SCIENCES P2 FISIESE WETENSKAPPE V2 MEMORANDUM MARKS/PUNTE: 150 This memorandum consists of 14 pages./ Hierdie memorandum bestaan uit 14 bladsye.

Downloaded from hlayiso.com 2 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/SEPTEMBER 2015) QUESTION/VRAAG 1 1.1 B  1.2 C  1.3 C  1.4 B  1.5 B  1.6 A  1.7 C  1.8 B  1.9 B  1.10 D  (10 x 2) (20) Copyright reserved Please turn over

Downloaded from hlayiso.com (E/CSEPTEMBER 2015) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 3 QUESTION 2/VRAAG 2 2.1 2.1.1 A and/en G  (1) 2.1.2 E (1) 2.1.3 B (1) CORRECT IUPAC NAME, BUT ONE OR MORE OF THE FOLLOWING ERRORS: OMITTING HYPHENS AND/OR COMMAS; INCLUDING EXTRA HYPHENS AND /OR SPACES MAX/MAKS ½ KORREKTE IUPAC-NAAM MAAR EEN OF MEER VD VOLGENDE FOUTE GEMAAK: WEGLATING VAN KOPPELTEKENS EN/OF KOMMAS; INSLUITING VAN EKSTRA SPASIES EN/OF KOPPELTEKENS 2.2 2.2.1   2-methylbut-2-ene ACCEPT 2-methyl-2-butene 2-metielbut-2-een AANVAAR 2-metiel-2-buteen (2) 2.2.2 haloalkane /alkyl halide haloalkaan/alkielhalied (1) -1 FOR STRUCTURAL FORMULA // -1 VIR STRUKTUUR FORMULE 2.2.3 2C2H2 + 5O2  → 4CO2 + 2H2O  balancing/balansering Notes/Aantekeninge: • Reactants Products Balancing:  Reaktanse Produkte Balansering • Ignore double arrows. / Ignoreer dubbelpyle. • Marking rule 6.3.10. / Nasienreël 6.3.10. (3) 2.3 2.3.1   CORRECT IUPAC NAME, BUT ONE OR MORE OF THE FOLLOWING ERRORS: OMITTING HYPHENS AND/OR COMMAS; INCLUDING ethyl methanoate EXTRA HYPHENS AND/OR SPACES MAX/MAKS ½ etielmetanoaat KORREKTE IUPAC-NAAM MAAR EEN OF MEER VD VOLGENDE FOUTE GEMAAK: WEGLATING VAN KOPPELTEKENS EN/OF KOMMAS; INSLUITING VAN EKSTRA SPASIES EN/OF KOPPELTEKENS (2) 2.3.2 -1 FOR CONDENSED H H STRUCTURAL FORMULA // -1 VIR GEKONDENSEERDE ǀ ǀ STRUKTUUR FORMULE H – C – C –O―H  FUNCTIONALGROUP/ | | FUNKSIONELE GROEP H H REST OF STRUCTURE/ RES VAN STRUKTUUR KORREK (2) 2.3.3 methanoic acid  metanoёsuur (1) Copyright reserved Please turn over

Downloaded from hlayiso.com 4 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/SEPTEMBER 2015) 2.4 Same molecular formula  C5H10O2  OR/OF C5O2H10 Dieselfde molekulêre formule Different structure /functional group Verskillende struktuur/funksionele group H H O H H O ǀ ǀ ǁ ǀ ǀ ǁ H–C–C–C–O–H  vs H – C – C –O – C ‒H ǀ ǀ ǀ ǀ H H H H (4) [18] Copyright reserved Please turn over

Downloaded from hlayiso.com (E/CSEPTEMBER 2015) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 5 QUESTION 3/VRAAG 3 3.1 3.1.1 Cracking /kraking (1) 3.1.2 addition (polymerisation) addissie (polimerisasie) (1) 3.1.3 -1 FOR CONDENSED STRUCTURAL H H FORMULA // -1 VIR GEKONDENSEERDE STRUKTUUR ǀ ǀ FORMULE n H ‒C= C‒ H → C –C | |  ǀ ǀ  H H H H n (3) 3.2 3.2.1 H Br H H ǀ ǀ ǀ | -1 FOR CONDENSED STRUCTURAL FORMULA H – C – C – C –C‒ H  -1 VIR GEKONDENSEERDE ǀ | | STRUKTUUR FORMULE H H H FUNCTIONALGROUP/ H ‒C‒H FUNKSIONELE GROEP REST OF STRUCTURE/ | RES VAN STRUKTUUR KORREK H (2) 3.2.2 addition /hydrobromination/hydrohalogenation addissie/hidrobrominering/hidrohalogenering (1) Copyright reserved Please turn over

Downloaded from hlayiso.com 6 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/SEPTEMBER 2015) 3.2.3 H H H ǀ I I H –C – C = C –C‒ H  + H-O  (H2O) → ǀ | I H H H H ‒C‒H | H H 1 FOR CONDENSED H O H H STRUCTURAL FORMULA ǀ ǀ ǀ | -1 VIR GEKONDENSEERDE H – C – C –C – C‒ H  STRUKTUUR FORMULE ǀ | | H H H FUNCTIONALGROUP FUNKSIONELE GROEP H ‒C‒H REST OF STRUCTURE | CORRECT H RES VAN STRUKTUUR KORREK (4) 3.2.3   2-methylbutan-2-ol ACCEPT 2-methyl-2-butanol 2-metielbutan-2-ol AANVAAR 2-metiel-2-butanol (2) 3.2.4 substitution  (hydrolysis) substitusie (hidrolise) (1) 3.2.5  use dilute potassium hydroxide /aqueous potassium hydroxide NaOH/strong base OR water  (mild) heat  OR hot ethanolic dilute base  gebruik verdunde kaliumhidroksied/waterige kaliumhidroksied NaOH/sterk basis OF water  (matige) hitte OF warm etanoliese verdunde basis (2) [17] Copyright reserved Please turn over

Downloaded from hlayiso.com (E/CSEPTEMBER 2015) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 7 QUESTION 4/VRAAG 4 4.1 The pressure exerted by a vapour at equilibrium with its liquid  in a closed system.  Die druk uitgeoefen deur ʼn damp in ewewig met sy vloeistof in ʼn geslote sisteem. (3) 4.2 4.2.1  Increased length of C chain /molecular size or structure/ molecular mass/surface area  Increased strength of InterMolecular Forces /London forces/dispersion forces/van der Waal’s forces  More energy required  to overcome IMF  Toename in lengte van C-ketting/molekulêre grootte of struktuur/ molekulêre massa/oppervlak area  Toename in sterkte van InterMolekulêre Kragte/London kragte/dispersie kragte/van der Waalskragte  Meer energie benodig om IMK te oorkom (3) 4.2.2 Butane  (1) 4.3 4.3.1 LOWER/LAER  (1) 4.3.2 Stronger  hydrogen bonds  between ethanol molecules OR London forces between ethane molecules are weaker than hydrogen bonds between ethanol molecules Sterker waterstofbindings tussen etanol molekules OF Londonkragte tussen etaan molekules swakker as waterstofbindings tussen etanol molekules (2) [10] Copyright reserved Please turn over

Downloaded from hlayiso.com 8 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/SEPTEMBER 2015) QUESTION 5/VRAAG 5 5.1 5.1.1 (a) rate of reaction/reaksietempo (1) (b) concentration/konsentrasie  (1) 5.1.2 As concentration of Na2S2O3 (aq) increases  (decreases), the time decreases  (increase)/rate of rxn decreases (increases). Soos die konsentrasie van Na2S2O3 (aq) toeneem (afneem), neem die tydsduur af (toe)/reaksietempo neem af (toe). (2) 5.1.3  1mol Na2S2O3 reacts with/reageer met 2 mol HCl   From/Vanuit : n= cV (0,5)(VNa2S2O3) =(0,5)(VHCl) n Na2S2O3 = n HCl   HCl  will therefore be the limiting reagent as we need twice the amount of HCl to react.  HCl is die beperkende reaktant omdat ons twee maal die hoeveelheid HCl benodig. (2) 5.2 5.2.1 Experiment 6  highest temperature  Eksperiment 6 hoogste temperatuur (3) 5.2.2 If the temperature of the reaction mixture increases:  Average kinetic energy higher  More particles have sufficient kinetic energy  to collide effectively  The number of effective collisions per unit time/second increases  The time lapse will decrease Rate of reaction increases As die temperatuur van die reaksiemensel toeneem:  Gemiddelde kinetiese energie hoër  Deeltjies het nou voldoende kinetiese energie om effektief te bots  Die aantal effektiewe botsings per tydseenheid/sekonde neem toe Die tydsverloop neem af Die reaksietempo neem toe (3) [12] Copyright reserved Please turn over

Downloaded from hlayiso.com (E/CSEPTEMBER 2015) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 9 QUESTION 6/VRAAG 6 6.1 6.1.1 yellow to orange  geel na oranje (1) 6.1.2 Cr2O72-  OR/OF dichromate ions/dichromaat-ione (1) 6.1.3 Exothermic  Eksotermies (1) Negative marking QUESTION 6.1.4 to QUESTION 6.1.5/Merk negatief 6.1.4  Increase in temperature favours endothermic reaction   The reverse reaction is favoured   The reverse reaction is endothermic  (forward) reaction is exothermic  Verhoging in temperatuur bevoordeel die endotermiese reaksie  Die terugwaartse reaksie word bevoordeel  Die terugwaartsewaartsereaksie is endotermies Die (voorwaartse) reaksie is exotermies (3) 6.2 6.2.1 H2 + I2 2HI Initial quantity (mol) 5 5 0 Aanvangshoeveelheid (mol) Change (mol)   x x 2x  Ratio/Verhouding Verandering (mol) Quantity at equilibrium (mol) 5-x 5-x 2x Hoeveelheid by ewewig (mol) Equilibrium concentration(mol∙dm-3) Ewewigskonsentrasie (mol∙dm-3) x  Dividing by 2 Deel deur 2 Copyright reserved Please turn over

Downloaded from hlayiso.com 10 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/SEPTEMBER 2015) [ ] Kc = [ ][ ]  ( ) 0,36=  ( )( ) x= [HI]=1,15 mol∙dm-3   USING ratio n(H2):n(I2):n(HI) = x:x:2x GEBRUIK verhouding n(H2):n(I2):n(HI)=x:x:2x Refer to rule 1.4 / Verwys na reël 1.4  Equilibrium n(H2) = initial n(H2)-change n(H2) Ewewig n(H2) = aanvangs n(H2)- verandering n(H2) Equilibrium n(I2) = initial n(I2)-change n(I2) Ewewig n(I2) = aanvangs n(I2)- verandering n(I2)  Equilibrium n(HI) = initial n(HI)-change n(HI) Ewewig n(HI) = aanvangs n(HI)- verandering n(HI)  Equilibrium moles divide by 2dm3 Ewewigs mol gedeel deur 2dm3  Correct Kc expression Korrekte Kc uitdrukking  Substitute Kc value into Kc expression Substitueer Kc waarde in Kc uitdrukking  Substitute concentrations into Kc expression Substitueer konsentrasies in Kc uitdrukking in  Final answer/Finale antwoord 1,15 mol∙dm-3 (8) 6.2.2 INCREASED/TOEGENEEM  Consider: c =  Same number of molecules occupy smaller volume  Beskou: c = Dieselfde aantal molekules beslaan ʼn kleiner volume (3) [17] Copyright reserved Please turn over

Downloaded from hlayiso.com (E/CSEPTEMBER 2015) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 11 QUESTION 7/VRAAG 7 7.1 Point where indicator changes colour  Punt waarby indicator van kleur verander (2) 7.2 M[KOH] = 39 + 16 + 1 = 56 g·mol-1 n = =  = 5 x 10-3 mol KOH na : nb is 2:1 5 x 10-3 mol KOH reacts with/reageer met 2,5 x 10-3 mol H2SO4  c =  = = 0,125 mol·dm-3  (5) 7.3 7.3.1 acid-base /protolysis/neutralisation suur-basis/protolise/neutralisasie (1) 7.3.2 HNO3 + NH3  → NH4NO3  balancing/balansering (3) 7.3.3 ACIDIC/SUUR  (1) 7.3.4 NH4NO3 + H2O →NH3 + H3O+ + NO3-  balancing/balansering Presence of excess H3O+ ions  makes solution acidic/ Teenwoordigheid van oormaat H3O+ veroorsaak dat oplossing suur is Accept/Aanvaar NH4+ + H2O  → NH3 + H3O+  balancing/balansering Presence of excess H3O+ ions  makes solution acidic/ Teenwoordigheid van oormaat H3O+ veroorsaak dat oplossing suur is (4) [16] Copyright reserved Please turn over

Downloaded from hlayiso.com 12 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/SEPTEMBER 2015) QUESTION 8/VRAAG 8 8.1 8.1.1  solution/liquid/dissolved substance that conducts electricity  through movement of ions    ʼn oplossing/vloeistof/opgeloste stof wat elektrisiteit gelei deur die beweging van ione (2) 8.1.2 H+  Accept/Aanvaar H2O/oxidation number of H decreases  from +1 to 0  H+ Anvaar H2O/oksidasiegetal neem af vanaf +1 tot 0 (3) 8.1.3 2 Cℓ → Cℓ2(g) + 2e-  2H2O +2e- → H2 + 2OH-  2Cℓ- + 2H2O → Cℓ2 + H2 + 2OH-  or/of 2NaCℓ + 2H2O → 2NaOH + Cℓ2 + H2 (4) 8.2 8.2.1 Ni(s)  (1) 8.2.2 Ni → Ni2+ + 2e-  Marking guidelines/Nasien riglyne: Ni2+ + 2e- Ni Ni Ni2+ + 2e- Ni2+ + 2e- ← Ni Ni2+ + 2e- → Ni (2) 8.2.4 LOWER /LAER Eθcell =Eθcathode - Eθanode  Accept any other correct formula from the data sheet. = 1,36  – (0,34)  = 1,02 V  Aanvaar enige ander korrekte formule vanaf gegewensblad. (5) [17] Copyright reserved Please turn over

Downloaded from hlayiso.com (E/CSEPTEMBER 2015) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 13 QUESTION 9/VRAAG 9 9.1 n(Cu) = n(electrons/elektrone) number of atoms = n x NA = (0,8 x 0,5)  x 6.02 x 1023  ( Cu2+ + 2e- → Cu) = 2,408 x 1023  atoms/atome (3) 9.2 OPTION/OPSIE 1 OPTION/OPSIE 2 n= n(Cu) = = = 0.441mol m(Cu) = nM n(Cu) (pure) = = = 0.4mol = 0,4 x 63,5  = 25,4g  % Cu = x 100 % Cu = x 100  = 90,70% = 90,71%  No/Nee  (% Cu ˂ 99,99%) No/Nee  (% Cu ˂ 99,99%) OPTION 3 Ncu (impure) = NA = x 6,02 = 2,654 x 1023 (atoms/atome) Ncu (pure) = = 2,41 x 1023  (atoms/atome) (% Cu = 2,41 x 10 23  2,65 x 10 23 = 90,9%  No/Nee  (% Cu ˂ 99,99%) (5) 9.3 Cu is a stronger reducing agent  than Pt and Ag and will be oxidised to Cu2+  Cu is ʼn sterker reduseermiddel as Pt en Ag en sal geoksideer word na Cu2+ OR/OF Pt and Ag are weaker reducing agents than Cu and Cu will be oxidised to Cu2+ Pt en Ag is swakker reduseermiddels as Cu en Cu sal geoksideer word na Cu2+ (3) [11] Copyright reserved Please turn over

Downloaded from hlayiso.com 14 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/SEPTEMBER 2015) QUESTION 10/VRAAG 10 10.1 10.1.1 Haber  (1) 10.1.2 N2 + 3H2  → 2NH3  balancing/balansering (3) 10.1.3 Iron or iron oxides  yster of ysteroksied (1) 10.2  Eutrophication is the process by which an ecosystem becomes enriched with inorganic plant nutrients (P and N)   This results in excessive plant growth/algal bloom   Decaying plant material uses up oxygen supply  in water  Leading to death of other aquatic plants and animals /dead zones  Eutrofikasie is die proses waartydens ʼn ekosisteem verryk word met ʼn oormaat anorganiese plant voedingstowwe (P en N)  Dit veroorsaak ʼn oormaat plantegroei/algebloei  Verrottende plant- en dieremateriaal gebruik die beskikbare suurstof in die water op  Wat lei tot dood van meer plante en diere/dooie sones (4) 10.3 10.3.1 Ferteliser A  (1) 10.3.2 Less nitrogen – prevents too much leaf growth at the cost of fruit  Richer in potassium- good quality flowers/fruit  Minder stikstof – voorkom oormaat blaargroei ten koste van vrugte Ryk aan kalium – verseker goeie kwaliteit blomme/vrugte (2) [12] TOTAL/TOTAAL: 150 Copyright reserved Please turn over

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