Physical Sciences Grade 11 Gauteng September Test 2023 QP

Downloaded from hlayiso.com Gawnloaded sfieacts Stanmorephysics. com SEPTEMBER 2023 JOHANNESBURG EAST DISTRICT This question paper consists Stanmorephysics Page 1 of 11

Downloaded from hlayiso.com Gaovnloaded strates Stanmorephysics.com SEPTEMBER 2023 10. INSTRUCTIONS AND INFORMATION Write your NAME and SURNAME on your ANSWER PAPER. Answer Att“questions. You may;usé a non-programmable calculator. You may use appropriate mathematical instruments. Number the answers according to the numbering system used in this question paper. An information sheet is attached for your use. Wherever motivation, discussion, et cetera is required, be brief. Start EACH question on a NEW page. Leave ONE line between two sub-questions, for example between QUESTION 2.1 and QUESTION 2.2. Show the formulae and substitutions used in all calculations. Round all numerical answers off to TWO decimal places. Page 2 of 11

Downloaded from hlayiso.com Geawnloaded sfrats Stanmorephysics.com SEPTEMBER 2023 QUESTION 1 1.1 Which ONE of the following statements CORRECTLY describes the characteristics of an endothermic reaction? A Atlis}positive and the products have less potential energy than the reactants. B AH-is!positive and the products have more potential energy than the reactants. Cc AH-iS negative and the products have less potential energy than the reactants D AH_is negative and the products have more potential energy than the reactants. (2) 1.2. Study the following graph and match label X from the following choices. a0 wo 4 200 4 Activation Energy Activated Complex Activation Complex Activated Energy (2) VOM 1.3. According to the kinetic-molecular theory, molecules of different gases at the same temperature always have the same A pressure B volume Cc kinetic energy D average kinetic energy. (2) 1.4 Which ONE of the following statements is CORRECT about an exothermic reaction? A The products have more energy than the reactants B The reactants release heat and therefore have less energy:than products Cc The heat of reaction is positive as the products have higher’energy D The reactants absorb heat and therefore the reaction container would feel cold. (2) Page 3 of 11

Downloaded from hlayiso.com Gawnloaded sfram: Stanmorephysics.com 1.5 Which ONE of the following combinations is correct for an endothermic reaction? HEAT OF REACTION (AH) THE POTENTIAL ENERGY OF PRODUCTS IS A | positive less than that of reactants B | positive more than that of reactants C | negative less than that of reactants D | negative more than that of reactants SEPTEMBER 2023 (2) 1.6 Which ONE of the following statements about a chemical reaction is CORRECT? The actual yield of a chemical reaction is usually ... A equal to the percentage yield. greater than the percentage yield. B Cc less than the theoretical yield. D greater than the theoretical yield. QUESTION 2 (Start on a new page.) A barium hydroxide solution, Ba(OH)2(aq), reacts with a nitric acid solution, HNO3(aq), according to the following balanced equation: Ba(OH)2(aq) + 2HNOsxeq) —» Ba(NO3)2(aq) + 2H20.) The potential energy graph below shows the change in potential energy for this reaction. > Potential energy (kJ-mol") wo a Leer Sane ws 116 kJ-mol" Course of reaction (2) 2.1 Is this reaction ENDOTHERMIC or EXOTHERMIC? Give a reason-for' the answer? (2) Page 4o0f 11

Downloaded from hlayiso.com Gaovnloaded strates Stanmorephysics.com SEPTEMBER 2023 2.2 Use energy values A, B and C indicated on the graph and write down an expression for each of the following: 2.2.1 The eneray of the activated complex (1) 2.23257 The activation energy for the forward reaction (1) 2/2;3)7 AH for the reverse reaction (1) 2.3 Calculate the amount of energy released during the reaction if 0,18 moles of Ba(OH)2(aq) reacts completely with the acid. (3) [8] QUESTION 3 (Start on a new page.) Hydrogen gas and oxygen gas react to form water according to the following balanced equation: 2Hag).+ Org) '2H20¢) + 241,8 kJ‘molt The activation energy (EA) for this reaction is 1 370 kJ‘mol* . 3.1 Define:the term activation energy. (2) 3.2 Sketch a potentialenergy versus reaction coordinate graph for the above reaction. Clearly label the axes and indicate the following on the graph: ° AH ¢ EA for the forward reaction ¢ Reactantsi(R) and products (P) e Activated complex (X) (5) 3.3. Write down the value of the: 3.3.1 Heat. of reaction (1) 3.3.2 Activation energy for the following reaction: 2H20(0) > 2Hag) + Ora) (2) [10] Page 5 of 11

Downloaded from hlayiso.com Gaovnloaded strates Stanmorephysics. com SEPTEMBER 2023 QUESTION 4 (Start on a new page) A fixed mass of oxygen is used to verify one of the gas laws. The results obtained are shown in the graph below ia PH OF VOLUME VERSUS PRESSURE 40| = i & : é 2 s rer 10] 4 50 100 150 200 250 Pressure (kPa) 4.1. Write down: 4.11 A mathematical expression, in symbols, for the relationship between the variables shown in the graph (1) 4.1.2 The name of the gas law investigated (1) 4.1.3 Explain the relationship in QUESTION 4.1.1 in terms of the kinetic theory of gases. (2) 4.2 Write down TWO variables that must be kept constant during this investigation and briefly describe how this is done. (4) 4.3 From the graph, write down the volume of oxygen, in cm?, when the pressure is 120 kPa. (2) 4.4 Calculate the pressure, in kPa, exerted on the gas when it is compressed to 5 cm’. (4) 4.5 Write down TWO conditions under which oxygen gas will devia m ideal gas behavior. (2) [16] Page 6 of 11

Downloaded from hlayiso.com Gaovnloaded strates Stanmorephysics.com SEPTEMBER 2023 QUESTION 5 (Start on a new page.) 5.1 Define the term mo/ar mass of a substance. (1) 5.2. Calculate thesnumber of moles of water in 100 g of water. (3) 5.3 Methyl benzoate is a compound used in the manufacture of perfumes. It is found that a 5,325 g sample of methyl benzoate contains 3,758 g of carbon, 0,316 g of hydrogen and 1,251 geofsoxygen. 5.3.1 5.3.2 5.3.3 Define the term empirical formula. (2) Determine the empirical formula of methyl benzoate. (7) If the molar mass of methyl benzoate is 136 g-mol?, what is its molecular formula? (3) [16] QUESTION 6 (Start on a new page.) 6.1 Iron (Fe) reacts with sulphur (S) to form iron sulphide (FeS) according to the following balanced equation: 6.1.1 6.1.2 Page 7 of 11 Fe(s) + S(s) — FeS Calculate which of the two substances will be used up completely if 20 g of Fe and 10 g of S are mixed and heated. (5) How many grams of the other substance are in excess? (2) [7]

Downloaded from hlayiso.com Gaovnloaded strates Stanmorephysics.com SEPTEMBER 2023 QUESTION 7 (Start on a new page.) 71 7.2 Limestone, or sometimes ash, is used in pit latrines (long drops) to neutralise acidic waste. Limestone reacts with hydrochloric acid according to the following UNBALANCED equation: CaCOxe) HIHChaq) > CaCloraq) + H20y + CO2,a) Fats Define an acid in terms of the Arrhenius theory (2) 7.1.2 Is ash acidic or basic? (1) 7.1.3 Rewrite the above equation into your ANSWER BOOK and then balance the equation. (1) Sulphuric acid reacts with water in two steps as represented by the equations below. Equation I H2SO4(aq) + H20.y) 2 H30* (ag) + HSO¢ - (aq) Equation II = HSO4" (aq) + H2O@ = H30* (aq) + SOz* (aq) 7.2.1 Define the term ampholyte. (2) 7.2.2 Write down the FORMULA of a species that acts as ampholyte in the above reactions. (1) 7.2.3 Write down the NAME of the conjugate base of the hydrogen sulphate ion. (1) [8] QUESTION 8 (Start on a new page) The chemical reaction for the production of the drug, aspirin, from two compounds, X and Y, is represented by the balanced equation below. 2C7H6O3 + CyHgO3 — 2CsHgO, + H20 A chemist reacts 14 g of compound X with 10 g of compound Y. 8.1 Define the term limiting reactant in a chemical reaction (2) 8.2 Perform the necessary calculations to determine which one of compound X or compound Y is the limiting reactant. (5) The actual mass of aspirin obtained is 11,5 g. 8.3 Calculate the percentage yield of the aspirin (5) [12] Page 8 of 11

Downloaded from hlayiso.com Gaovnloaded strates Stanmorephysics.com SEPTEMBER 2023 QUESTION 9 (Start on a new page.) Acids and bases can be defined in terms of the following two theories: 9.1 9.2 9.3 I: Arrhenius-theory II: Lowry;Brénsted theory According torthe Arrhenius theory, sodium hydroxide is classified as a base. Write down the chemical formula of the ion responsible for the basic properties of sodium hydroxide. (1) Consider the reaction represented by the incomplete equation below: HNOs3(aq) + OH" (aq) = + 9.2.1 Use your knowledge of the Lowry-Brénsted theory to write a balanced equation for this reaction. (3) 9.2.2 Write down the formulae of ONE conjugate acid-base pair in this reaction. (2) In a reaction, 40 cm? of nitric acid neutralises 25 cm? of a 0,05 mol-dm® solution of barium hydroxide according to the following balanced equation: 2HNO3(aq) + Ba(OH)2(aq) > Ba(NOs3)a(aq) + 2H20(2) Calculate the: 9.3.1 Number of moles of base that reacted (2) 9.3.2 Number of moles of acid that reacted (1) 9.3.3 Concentration of the acid (2) [11] GRAND TOTAL 100 Page 9 of 11

Downloaded from hlayiso.com Gaovnloaded strates Stanmorephysics.com SEPTEMBER 2023 NATIONAL SENIOR CERTIFICATE NASIONALE SENIOR SERTIFIKAAT DATA FOR PHYSICAL SCIENCES GRADE 11 im PAPER 2 (CHEMISTRY) a /O00/|GEGEWENS VIR FISIESE WETENSKAPPE GRAAD 11 oi VRAESTEL 2 (CHEMIE) =— TABLE 1: PHYSICAL CONSTANTS/TABEL 1: FISIESE KONSTANTES NAAM/NAME SIMBOOL/SYMBOL WAARDE/ VALUE Standard pressure p° 1,013 x 10° Pa Standaarddruk Molar gas volume at STP Vn 22,4 dm*-mol* Molére gasvolume teen STD Standard temperature Te 273K Standaardtemperatuur Charge on electron e 16x10%C Lading op elektron Avogadro's constant Na 6,02 * 1073 molt Avogadro se konstante TABLE 2: FORMULAE/TABEL 2: FORMULES = = orlof c=2 orlof c= pH= -log[H30*] Kw=[HsO*][OH] = 1x10-4 at /by 298K n= = orlof CaVa =a ¥ m CyVb Nb _v nev E®cen = E®cathode—E® anode / E%set = E®katode—E® anode E® cot = E® reduction —E oxidation / E8set = E®reduksie—E“oksidasie dot £0007 E% cet = EP axidising agent—E®reducing agent / E%sei = E®ksideermiddet-E"reduseermitaain) —5 Page 10 of 11

Downloaded from hlayiso.com Gawnloaded sfram: Stanmorephysics.com SEPTEMBER 2023 TABLE 3: THE PERIODIC TABLE OF ELEMENTS/TABEL 3: DIE PERIODIEKE TABEL VAN ELEMENTE 1 2 3 4 5 6 7 8 9 10 11 12 13 14 415 16 17 18 ) tH Atoomgetal tt) Iv VI Vil tI) 0 KEYI SLEUTEL atomic manber (ml) (IM) (¥) (I) (VI) (vit) < 1 | Z aH He 1 a |. 5 4 3 rT Elektronegatiwiteit_ Jo Cy le imboo! 5 6 7 | “8SS/9/ | 10 @1i|% Be Fotmeniy as | Se Mcn Boer} ne 7 9 11 12 14 16 19 20 a a 12 f é 13 a 14 15 a 16 is 17 18 > Nal Mg Benaderde relatiewe atoommassa AG |S Si ~ pies ce Ar e 93\" 24 Approximate relative atomic mass o7 | 28 iN 31 Nn 30 ° 35.5 40 19) 20 21) 22) 23] 24) 25) 26) 27| 28) 29 30 | 34 32 | 33 34] 35 36 SK |S ca |% sc f2 1/2 v |S cr [2 mn|2 Fe |2co|2 ni |% cu | zn |& Ga |Z Ge |Z As |% Se |S Br | Kr 39; 40 45| 48) 51 52 55| 56) 59) 59) 63,5) 65 70 73 75 79 80 84 a 37 = 38 39 4 41 as 42| 43] 44) 45| 46| 47 48 49 i 50 51 52 ia 53 54 GRbIS Sr SY [Eze Nb|S Mo |% Te |M Ru |eRh|Y Pd |® Ag |= Ca | In [2 Sn |@ Sb |G Te ly 1 | Xe 86 88 89| 91) 92 96 101| 103) 106) 108| 112| 115] 119| 122; 128| 127| 134 55) 56 57| 72) 73) 74) 75] 76) 77) 78| 79 80 | 81 82 | 83 84] 85 86 Cs/2 Ba) Lal bf) Ta) W] Re| Os| Ir| Pt} Au| Hg |® Te |@ Pb |@ Bi [2 Po|@ At | Rn 133 137| 139) 179) 181] 184] 186) 190) 192) 195} 197| 201) 204) 207} 209 87) 88 89 Nr @ o Fig Ra) Ac 5] 59 | 60 | 61 | 62] 63] 64 | 65 | 66 | 67 | 68 | 6] 70) 74 Ce | Pr | Nd | Pm | Sm| Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu 140 | 141 | 144 150 | 152 | 157 | 159 | 163 | 165 | 167 | 169 | 173 | 175 90 | 91 92 | 93 | 94 | 95 | 96 97 | 98 99 | 100 | 101 | 102 | 103 Th Pa U Np | Pu | Am| Cm | Bk Cf Es | Fm | Md | No Lr 232 238 Page 11 of 11