Physical Sciences Grade 11 P2 2015 Memo

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE/GRAAD 11 NOVEMBER 2015 PHYSICAL SCIENCES P2/ FISIESE WETENSKAPPE V2 MEMORANDUM MARKS/PUNTE: 150 This memorandum consists of 9 pages./ Hierdie memorandum bestaan uit 9 bladsye.

Downloaded from hlayiso.com 2 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/NOVEMBER 2015) QUESTION 1 / VRAAG 1 1.1 D √√ 1.2 C √√ 1.3 C √√ 1.4 C √√ 1.5 A √√ 1.6 A √√ 1.7 B √√ 1.8 C √√ 1.9 D√ 1.10 B √√ (10 x 2) [20] QUESTION 2 / VRAAG 2 2.1 2.1.1 C√ 2.1.2 E√ 2.1.3 D√ 2.2 A √ and/en D √ 2.3.1 √√ (2) 2.3.2  Electronegativity difference 1 √√ / ( C-2.1 and O-3.5 ) Verskil in elektronegatiwiteit  Uneven √ sharing of electron pairs √ / O-atoms have stronger pull on shared electron pairs. Onewe deel van elektronpare / O-atome trek gedeelde elektronpare sterker aan. (4) [11] Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/NOVEMBER 2015) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 3 QUESTION 3 / VRAAG 3 3.1 3.1.1 Induced-dipole induced dipole √ / London / dispersion forces Geїnduseerde-dipool geїnduseerde dipool / London dispersiekragte (1) 3.1.2 hydrogen bonds √ / waterstofbindings (1) 3.1.3 ion-dipole forces √ / ion-dipool kragte (1) 3.2 3.2.1  Strong H-bonds between molecules √  Large amount of energy absorbed for small change in temperature √  Sterk H-binding tussen molekule  Groot hoeveelheid energie word vir ʼn klein toename in temperatuur geabsorbeer. 3.2.2  Moderate climate close to large bodies of water √ / organisms can maintain steady body temperatures.  Gematigde klimaat naby groot wateroppervlaktes / organismes kan ʼn konstante liggaamstemperatuur onderhou. 3.2.3  Each molecule of water surrounded by 4 others √ / 3D-tetrahedral shape  Structure with large open spaces. √  Elke molekuul omring deur 4 ander watermolekules/ 3-D tetrahedrale vorm  Struktuur met groot oop spasies. 3.2.4  Water freezes from top down − capturing heat √ / aquatic organisms stay alive below ice.  Water vries van bo na onder – vang hitte vas / akwatiese organismes bly lewend onder die water. 3.2.5  Strong adhesive forces √√  Sterk adhesiekragte 3.2.6  Water moves upward/and sideways √ to top branches and leaves / photosynthesis / transpiration.  Water beweeg op- en sywaarts na boonste take en blare/ fotosintese / transpirasie. (9) [12] Copyright reserved Please turn over

Downloaded from hlayiso.com 4 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/NOVEMBER 2015) QUESTION 4 / VRAAG 4 4.1 4.1.1 bond length √ / bindingslengte (1) 4.1.2 bond energy √ / bindingsenergie (1) 4.1.3 NO √ / NEE (1) 4.1.4 Negative marking/Negatiewe merk or there is more than one independent variable√√  The variables are not controlled √ / Die veranderlikes word nie konstant gehou nie  Bonds should be between atoms of the same elements √ / Bindings moet tussen atome van dieselfde elemente wees (2) 4.2 4.2.1 Energy required: 4x C-H √ = 4 x 413 = 1 652 √ 2x O=O √ = 2 x498 = 996 √ (4) 4.2.2 Energy released: 2 x C=O √ = 2 x 804 = 1608 √ 4x H-O √ = 4 x 463 = 1852 √ (4) 4.2.3 ΔH = (1 652 + 996) − (1 852 + 1 608) = 2648 – 3460 √ = -812 kJ √ (2) activated complex √ geaktiveerde kompleks 4.2.4 -1 Enthalpy (kJ∙mol Y-axis√ labelling )/ Enthalpy (kJ∙mol-1 X-axis√ labelling )/ √ shape Ea √ Ea √ Act complex √ √ CH4+ 2O2 Shape √ Entalpie Entalpie √ CO2 +2H2O ΔH√ Progress of the reaction √ / Verloop van reaksie Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/NOVEMBER 2015) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 5 4.3.1 n= √= mol √ 1 mol CH3OH : 2 mol H2 √ 3,906 mol : 7,8125 V =nVm √ = 7,8125 x 22,4 √ = 175 dm3 √ (7) 4.3.2 √ x 100% √ = 85,71% √ (3) [31] QUESTION 5 / VRAAG 5 5.1 5.1.1 A√ (1) 5.1.2  consider/beskou: D = = √  If molar mass (M) and volume (V) is the same √ -– then D n √ As die molêre massa (M) en volume (V) dieselfde is – dan is D n  Gas A has more particles than gas B √ / Gas A het meer deeltjies as gas B.  More collisions with sides of container A √ Exert greater pressure in A. Meer botsings met die kante van houer A ʼn Groter druk word in A uitgeoefen. (5) 5.2 n= = 0,525 mol √ pV = nRT =( )( )( ) = 226 192,799 Pa √ = 226,19 kPa Yes, it will take the strain. √ / Ja, dit sal die spanning kan weerstaan. (7) Copyright reserved Please turn over

Downloaded from hlayiso.com 6 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/NOVEMBER 2015) 5.3.1 pV √√ shape/vorm T (2) 5.3.2 GREATER THAN / GROTER AS √ (1) 5.3.3 Particles of a real gas have volume √√ / there are repulsive forces between particles of a real gas Ware gasdeeltjies het volume / daar is afstotende kragte tussen die deeltjies van ʼn ware gas. (2) [18] QUESTION 6 / VRAAG 6 6.1 M(Na2SO4) = 142 g∙mol-1 √ 15 – 7,05 = 7,95g √ Na2SO4 n = = = 0,0559 mol √ Na2SO4 n = = = 0,392 mol √ H2O Ratio 1 : 7 √ (5) 6.2 6.2.1 in 100 g: = 3,325 mol C √ = 6,7 mol H√ = 3,3375 mol O √ Ratio: C1H2O1 √ -1 M(C1H2O1) = 12 + 2(1)+16 = 30 g∙mol √ and 60/30 = 2 Molecular formula / molekulêre formule: C2H4O2 √ (6) Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/NOVEMBER 2015) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 7 6.2.2 acid donates √ 1 H+ ion √ / suur doneer (skenk) 1 H+ ion (2) 6.3 6.3.1 2HCℓ + CaCO3 √ CaCℓ2 + CO2 + H2O √√ balancing/balansering (3) 6.3.2 M(CaCO3) = 40 + 12 + 3(16) = 100 g∙mol-1 √ n= = = 0,005 mol √ CaCO3 1 mol CaCO3 : 2 mol HCℓ therefore/dus 0,005 : 0,01 mol HCℓ √ M(HCℓ) = 1 + 35,5 = 36,5 g∙mol-1 √ M = nM = 0,01(36,5) = 0,365 g = 365 mg √ stomach acid/maagsuur (6) [22] QUESTION 7 / VRAAG 7 7.1 7.1.1 loss of electrons √√ / verlies aan elektrone (2) 7.1.2 MnO 2+ √ Aℓ2O3 3+ √ 7.1.3 MnO √ Mn2+ reduced √ to / gereduseer na Mn decrease √ in oxidation numbers/ afname in oksidasiegetal OR oxidation number of Mn decreases from +2 to 0. √√ / OF oksidasiegetal van Mn neem af van +2 na 0. (3) 7.2 n= = = 3,7 mol Aℓ √ n= = = 2,82 mol MnO √ Aℓ : MnO ratio 2 : 3 1,88 mol Aℓ : 2,82 mol MnO √ Aℓ in excess and MnO the limiting reagent. √ / Aℓ in oormaat en MnO is die beperkende reagens (5) 7.3 7.3.1 Cu → Cu2+ + 2e- √ Mark positively / 4H+ + NO3- + 3e- → NO + 2H2O √√√ Merk positief (4) 7.3.2 Cu → Cu2+ + 2e- (x3) √ 4H+ + NO3- + 3e- → NO + 2H2O (x2) √ + 3- 2+ 3Cu + 8H + 2NO √ → 3Cu + 2NO + 4H2O √ (4) [20] Copyright reserved Please turn over

Downloaded from hlayiso.com 8 PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 (EC/NOVEMBER 2015) QUESTION 8 / VRAAG 8 8.1 The earth’s crust and upper mantle / Die aardkors en boonste mantel √ (1) 8.2 As minerals / mineral ores √ (1) 8.3 8.3.1 ANY TWO / ENIGE TWEE / o.a.o.  Money / gold bullion √ – valuable as it does not stain / corrode √ Geld / valuta − slaan nie aan of vlek nie.  Decoration √ − malleable / can be rolled out in foils √ Versiering − pletbaar/ kan in dun goudfoelie gerol word  Heat shield on spacecrafts √ – reflect sunlight √ / lustre Hitteskild op ruimtetuie- weerkaats sonlig / metaalglans  Heating elements in aeroplane windows √ − reflect sunlight √ Verhittingselemente in vliegtuigvensters − weerkaats sonlig / metaalglans  Jewellery √ − can be alloyed with cheaper metals to retain shape. √ Juwele − kan in allooi gemaak word met goedkoper metale wat vormbestand is.  Electronic circuits √ − good conductor of electricity √ Elektroniese stroombane − goeie geleier van elektrisiteit  Gold implants e.g. gold crowns in dentistry √ − will not rust /react with bodily fluids √ / bio-compatible.  Goue ingeplante bv. goue krone in tandheelkunde − roesbestand en sal nie reageer met liggaamsvloeistowwe / bio-aanpasbaar. (4) 8.3.2 M(NH4NO3) = 2(14) + 4(1) + 3(16) = 80 g∙mol-1 √ n= = = 4 mol NH4NO3 √ 2 mol NH4NO3 : 7 mol gas 4 mol : 14 mol gas √ V= nVm= 14 (22,4) √ = 313,60 dm3 = 313,6 l of gas √ (5) Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/NOVEMBER 2015) PHYSICAL SCIENCES P2/FISIESE WETENSKAPPE V2 9 8.3.3 ANY TWO / ENIGE TWEE / o.a.o.  Large areas of land deforested and water extracted – soil not suitable for agricultural use / leads to erosion. Groot dele skoongemaak van plantegroei en water onttrek − grond nie geskik vir landbou / lei tot erosie.  Water tables lowered – could lead to formation of sinkholes Watertafels verlaag − kan lei tot sinkgatvorming.  Huge rocks removed and relocated/ mine dumps and tailing dams. Groot rotse word verwyder en verplaas / mynhope en afloopdamme.  Silt containing heavy metals e.g. arsenic, cadmium and cobalt / radioactive particles. Slyk bevat swaarmetale bv. arseen, kadmium en kobalt / radioaktiewe deeltjies.  Mudslides / modderstortings  Cyanide and sulphuric acid leaching into groundwater. / Sianied en swawelsuur loog uit in grondwater in.  Acid mine drainage enters groundwater − unfit for consumption. Suurmyndreinering gaan in grondwater in − nie geskik om te drink nie. (2) 8.4  Crushed ore placed in tank with aqueous sodium cyanide √ Fyngemaakte erts word in ʼn tenk met waterige natriumsianied geplaas  In the presence of air (O2) a pulp is formed √ / oxidation takes place In die teenwoordigheid van lug word ʼn pulp gevorm / oksidasie vind plaas  Gold forms a soluble ion √  Goud vorm ʼn oplosbare ioon. (3) [16] TOTAL/TOTAAL: 150 Copyright reserved Please turn over