Physical Sciences Grade 11 KZN September Test 2024 QP & Memo

Downloaded f rom St anmorephysics. com NATIONAL SENIOR CERTIFICATE GRADE 11 PHYSICAL SCIENCES COMMON TEST SEPTEMBER 2024 TIME: 2 hours MARKS: 100 This question paper consists of 8 pages and two data sheets. Copyright reserved Please turn over

Downloaded f rom St anmorephysics. Physical Sciences 2 com September Common Test 2024 NSC INSTRUCTIONS AND INFORMATION TO CANDIDATES 1. Write your name on the ANSWER BOOK. 2. This question paper consists of SEVEN questions. Answer ALL the questions in the ANSWER BOOK. 3. Start EACH question on a NEW page in the ANSWER BOOK. 4. Number the answers correctly according to the numbering system used in this question paper. 5. Leave ONE line between two subsections, for example between QUESTION 2.1 and QUESTION 2.2. 6. You may use a non-programmable calculator. 7. You may use appropriate mathematical instruments. 8. You are advised to use the attached DATA SHEET. 9. Show ALL formulae and substitutions in ALL calculations. 10. Round off your final numerical answers to a minimum of TWO decimal places. 11. Give brief motivations, discussions, et cetera where required. Copyright Reserved Please Turn Over

Downloaded f rom St anmorephysics. Physical Sciences 3 com September Common Test 2024 NSC QUESTION 1 Four options are provided as possible answers to the following questions. Each question has only ONE correct answer. Write only the letter (A - D) next to the question number (1.1 — 1.5) in the ANSWER BOOK, for example 1.6 D. 1.1 The number of hydrogen atoms in one mole of ammonia (NH3) is… A 3 B 1,204 x 1024 C 1,806 x 1024 D 6,02 x 1023 (2) 1.2 Which ONE of the following gases occupies the largest volume at STP? A 32 g of O2(g) B 34 g of NH3(g) C 7 g of N2(g) D 4 g of He(g) (2) 1.3 Real gas behaviour deviates from ideal gas behaviour at… A Low temperatures and low pressures B Moderate temperatures and high pressures C Moderate temperatures and low pressures D Low temperatures and high pressures (2) 1.4 In a chemical reaction, the difference between the potential energy of the products and the potential energy of reactants is equal to: A Enthalpy of the reaction B Rate of the reaction C Enthalpy change of the reaction D Total potential energy of the particles (2) 1.5 Which ONE of the following is the correct description of a solution of hydrochloric acid of concentration 0,1 mol∙dm-3 ? A Dilute strong acid B Dilute weak acid C Concentrated strong acid D Concentrated weak acid (2) [10] Copyright Reserved Please Turn Over

Downloaded f rom St anmorephysics. Physical Sciences 4 com September Common Test 2024 NSC QUESTION 2 2.1 Define the term molar mass. (2) 2.2 Calculate the percentage of carbon in cane sugar C12H22O11. (2) 2.3 CxHy is a compound made up of carbon (C) and hydrogen (H) only. 1,97g of this compound reacts with excess O2 (g) to produce 6,2g of CO2 (g). Determine the empirical formula of this compound. (6) 2.4 A metal M forms two chlorides, MCℓ2 and MCℓx, that contain 55,9% and 65,5% chlorine by mass respectively. Determine the: 2.4.1 Relative atomic mass of M (4) 2.4.2 Value of x. Show all working. (4) [18] QUESTION 3 In an experiment, a 300 cm3 solution of hydrochloric acid (HCℓ) of concentration 0,5 mol.dm-3 reacts with calcium carbonate powder. The HCℓ is in excess. The following balanced reaction takes place at 250C. CaCO3(s) + 2HCℓ(aq) → CaCℓ2(aq) + H2O(ℓ) + CO2(g) The volume of carbon dioxide gas produced is measured at regular time intervals and the following graph is drawn: 2 4 6 12 Time (minutes) 3.1 Define the term concentration. (2) 3.2 Give a reason why the graph is horizontal after 6 minutes. (1) Copyright Reserved Please Turn Over

Downloaded f rom St anmorephysics. Physical Sciences 5 com September Common Test 2024 NSC 3.3 Determine the maximum number of moles of carbon dioxide gas (CO2) produced. Take the molar gas volume at 25°C to be 24000cm3. (3) 3.4 Calculate the concentration of the HCℓ solution after 6 minutes. Assume that the volume of the solution remains at 300 cm3. (7) [13] QUESTION 4 4.1 A laboratory assistant prepares a solution of calcium nitrate of volume 250cm 3 using Ca(NO3)2∙4H2O (s) as the solute: Ca(NO3)2 → Ca2+(aq) + 2NO3- (aq) If the concentration of the nitrate ions in the solution is 0,15 mol∙dm-3, calculate the mass of solute that the laboratory assistant used. (5) 4.2 The chemical reaction for the production of aspirin(C9H8O4), from salicylic acid (C7H6O3) and acetoacetic acid(C4H6O3), is represented by the balanced equation below. 2C7H6O3 + C4H6O3 → 2C9H8O4 + H 2O aspirin A chemist reacts 14 g salicylic acid with 10 g of acetoacetic acid. 4.2.1 Define limiting reagent. (2) 4.2.2 By means of a suitable calculation, determine which of the reactants is the limiting reagent. (4) 4.2.3 The actual mass of aspirin obtained at the end of the reaction is 11,5 g. Calculate the percentage yield of this reaction. (5) [16] Copyright Reserved Please Turn Over

Downloaded f rom St anmorephysics. Physical Sciences 6 com September Common Test 2024 NSC QUESTION 5 A group of learners perform an experiment to verify a gas law. The results of the experiment are shown in the graph of pressure vs the inverse of volume drawn below. 1 x 10-2 cm-3 volume 5.1 NAME the law being verified. (1) 5.2 Write down an investigative question for this experiment. (2) 5.3 Name TWO variables that must be kept constant during the experiment. (2) 5.4 Calculate the volume occupied by the gas when the pressure exerted by the gas is 200kPa. (3) 5.5 Determine the pressure exerted by the gas when its volume is 11,11cm3 (3) 5.6 State 2 properties of an Ideal Gas (2) [13] Copyright Reserved Please Turn Over

Downloaded f rom St anmorephysics. Physical Sciences 7 com September Common Test 2024 NSC QUESTION 6 The graph below shows the energy changes for a certain reaction. Study the graph, and answer the questions that follow. 6.1 Is the reaction EXOTHERMIC or ENDOTHERMIC? Give a reason for the answer. (2) 6.2 Define the term activation energy. (2) 6.3 Write down the values for the: 6.3.1 Energy of the reactants (1) 6.3.2 Energy of the products (1) 6.3.3 Activation energy for the reverse reaction (1) 6.3.4 Activation energy for the catalysed forward reaction (1) 6.3.5 Energy of the activated complex in the absence of a catalyst (1) 6.4 Calculate the heat of reaction, (∆H), for the reverse reaction. (2) 6.5 What effect will the addition of the catalyst have on: (Choose from INCREASES, DECREASES or REMAINS THE SAME) 6.5.1 The energy of the products? (1) 6.5.2 The heat of reaction? (1) 6.5.3 The activation energy for the reverse reaction? (1) [14] Copyright Reserved Please Turn Over

Downloaded f rom St anmorephysics. Physical Sciences 8 com September Common Test 2024 NSC QUESTION 7 7.1 Given the following acid-base reaction: NH3 + H3PO4 ⇌ NH4+ + H2PO4 - 7.1.1 Define a base according to the Lowry-Bronsted theory. (1) 7.1.2 Identify the TWO bases in the above reaction. (2) 7.1.3 Define the term ampholyte. (2) 7.1.4 Write down the FORMULA of an ampholyte in the above reaction. (1) 7.2 A learner reacts 20 cm3 of a 0,2 mol∙dm-3 solution of sodium carbonate, completely with 12 cm3 of hydrochloric acid solution. The balanced equation for this reaction is: Na2CO3 + 2HCℓ → 2NaCℓ + CO2 + H2O Calculate the: 7.2.1 Number of moles of Na2CO3 that reacted. (3) 7.2.2 Concentration of the hydrochloric acid solution. (4) 7.2.3 pH of the hydrochloric acid solution before it reacted. (3) [16] TOTAL : 100 Copyright Reserved Please Turn Over

Downloaded f rom St anmorephysics. Physical Sciences 9 com September Common Test 2024 NSC DATA FOR PHYSICAL SCIENCES GRADE 11 PAPER 2 (CHEMISTRY) TABLE 1: PHYSICAL CONSTANTS/TABEL 1: FISIESE KONSTANTES NAAM/NAME SIMBOOL/SYMBOL WAARDE/VALUE Standard pressure p 1,013 × 105 Pa Standaarddruk Molar gas volume at STP Vm 22,4 dm3∙mol-1 Molêre gasvolume teen STD Standard temperature Tθ 273 K Standaardtemperatuur Charge on electron e 1,6 × 10-19 C Lading op elektron Avogadro’s constant NA 6,02 × 1023 mol-1 Avogadro se konstante TABLE 2: FORMULAE/TABEL 2: FORMULES m n m n= M c= V c = MV p1V1 = p2V2 N cA VA nA n= N = A cB VB nB V n= Vm Copyright Reserved Please Turn Over

Downloaded f rom St anmorephysics. Physical Sciences 10 com September Common Test 2024 NSC Copyright Reserved Please Turn Over

Downloaded f rom St anmorephysics. com Education KwaZulu-Natal Department of Education REPUBLIC OF SOUTH AFRICA PHYSICAL SCIENCES MARKING GUIDELINES COMMON TEST SEPTEMBER 2024 NATIONAL SENIOR CERTIFICATE GRADE 11 NB: This marking guideline consists of 6 pages. Copyright reserved Please turn over

Downloaded Physical Sciences f rom St anmorephysics. 2 com September 2024 Common Test NSC QUESTION ONE 1.1 C  1.2 B  1.3 D  1.4 C  1.5 A  [10] QUESTION TWO 2.1 The mass of one mole of a substance.  (2) 2.2 M (C12H22O11) = 12(12) + 22(1) + 11(16) = 144 + 22 + 176 = 342 g.mol-1  % C = 144 x 100 = 42,11%  342 (2) 2.3 Mass of C in 6,2g of CO2: 12 44 ×6,2 = 1,69g C H ∴ mass of C in CxHy is 1,69 g Mass 1,69 g 0,28 g Mass of H in CxHy = 1,97 – 1,69 = 0,28g n = m/M 1,69 0,28 12 1 = 0,14 = 0,28 Divide by 0,14 0,28 smallest 0,14 0,14 Ratio 1 2 Empirical formula is CH2 (6) 2.4.1 M  71 ×100 = 44,1 OR ×100 = 55,9 M+71  M+71  M = 56 g·mol-1 (4) 2.4.2 x(35,5) 65,5 56+x(35,5) =  100 x = 3 (4) [18] Copyright reserved Please turn over

Downloaded Physical Sciences f rom St anmorephysics. 3 com September 2024 Common Test NSC QUESTION 3 3.1 The amount of solute per dm3 of solution. / The number of moles of a substance per unit volume.  (2) 3.2 No more carbon dioxide is produced. / The reaction has ended / All the (1) CaCO3 has reacted. 3.3 V n=  Vm = 500  24000 = 0,0208 mol  (3) 3.4 POSITIVE MARKING FROM 3.3 MARKING CRITERIA: • Substitution / answer: calculation of initial moles of HCl.  • Apply ratio of moles of HCl to CO2.(2:1).  • Subtracting moles that reacted from initial moles of HCl.  • Formula to calculate concentration.  • Substitution into concentration formula.  • Final answer.  OPTION 1 (7) ni = cV = 0,5 x 0,3 n = 0,15 mol c=  V = 0,1084 nreacted = 2 x 0,0208 = 0,0416 mol 0,3 = 0,361 mol.dm-3 nexcess = ni - nreacted = 0,15 – 0,0416 = 0,1084 mol OPTION 2 CaCO3 2HCI CaCI2 H2O CO2 Ratio 1 2 1 1 1 Initial 0,15  0 Change -0,0416  0,0208 End 0,1084  [13] Copyright reserved Please turn over

Downloaded Physical Sciences f rom St anmorephysics. 4 com September 2024 Common Test NSC QUESTION 4 4.1. n (NO3-) =CxV = 0,15 x 0,25  = 0,0375 mol n (Ca(NO3-)) = ½(0,0375)  = 0,01875 mol ∴ mass of Ca(NO3)2·4H2O used m = nM  = 0,01875(164 +4(18))  = 4,425 g (5) 4.2.1 The reactant that is used up first/completely in a chemical reaction.  (2) OR the reactant that determines the amount of product that is formed m m 4.2.2 n (C7H6O3) = n (C4H6O3) = M M = 14  = 10  138 102 = 0,10 mol = 0,10 mol From balanced equation: n(C7H6O3) : n(C4H6O3) 2 : 1 ∴ 0,1 mol of C7H6O3 needs 0,05 mol of C4H6O3  ∴ The limiting reactant is C7H6O3  (4) m 4.2.3 n (C9H8O4) = M % yield = actual yield x 100 theoretical yield m 0,1 = 180 11,5 = × 100  18 ∴m = 18 g (18,26 g)  = 63,90% (62,98%) (5) [16] Copyright reserved Please turn over

Downloaded Physical Sciences f rom St anmorephysics. 5 com September 2024 Common Test NSC QUESTION 5 5.1 Boyle’s Law  (1) 5.2 What is the relationship between the pressure exerted and the volume occupied by a fixed mass of (dry) gas at constant temperature?  (2) 5.3 Mass (of gas)  or Temperature (of gas) (2) 5.4 At 200kPa 1/v = 6,7 x 10-2  ∴v= 1  6,7 x 10-2 v = 14,93 cm-3  (3) 5.5 p1v1 = p2v2 120(25) = p2 (11,11)  (or any other correct combinations for p1 and v1 from the graph) p2 = 270,03 kPa (3) 5.6 The particles of the ideal gas: (any 2) • Occupy no volume. • Are identical in all ways. • Exert no forces on each other except during a collision. • All collisions between gas molecules are completely elastic. (2) [13] QUESTION 6 6.1 Exothermic. ΔH < 0  / Eproducts < Ereactants (2) 6.2 The minimum energy needed for a reaction to take place (2) 6.3.1 208,2 kJ (1) 6.3.2 86,5 kJ (1) 6.3.3 154,3 kJ OR 130,8 kJ (1) 6.3.4 9,1 kJ (1) 6.3.5 240,8 kJ (1) 6.4 ΔH = Eproducts - Ereactants = 208,2 – 86,5  = 121,7 kJ (2) Copyright reserved Please turn over

Downloaded Physical Sciences f rom St anmorephysics. 6 com September 2024 Common Test NSC 6.5.1 Remains the same . (1) 6.5.2 Remains the same. (1) 6.5.3 Decreases. (1) [14] QUESTION 7 7.1.1 A base is a proton acceptor.  (1) 7.1.2 NH3  and H2PO4 -  (2) 7.1.3 A substance that acts as an acid and base.  (2) 7.1.4 H2PO4 -  (1) 7.2.1 n (Na2CO3) = c x V  = 0,2 x 0,02  = 0,004 mol  (3) 7.2.2 POSITIVE MARKING FROM QUESTION 7.2.1 OPTION 1: OPTION 2: n (Na2CO3) : n (HCI) 1 : 2 cA VA nA ∴ n (HCI) = 2 x 0,04 = 0,008 mol = cB VB nB n  c= cA ×12 2 v =  = 0,008  0,2 ×20  1 0,012  cA = 0,67 mol·dm-3 = 0,67 mol.dm-3  (4) LEAVE OUT (FORMULA NOT GIVEN IN DATA SHEET) Refer to conversion sheet for question 7 7.2.3 pH = -log[H30+]  = - log (0,67)  = 0,17  (3) [16] TOTAL: 100 Copyright reserved Please turn over