Technical Sciences P2 May June 2022 Eng hlayiso.com

Downloaded from hlayiso.com SENIOR CERTIFICATE EXAMINATIONS/ NATIONAL SENIOR CERTIFICATE EXAMINATIONS TECHNICAL SCIENCES P2 2022 MARKS: 75 TIME: 1½ hours This question paper consists of 9 pages and 4 data sheets. Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 2 DBE/2022 SC/NSC INSTRUCTIONS AND INFORMATION 1. Write your centre number and examination number in the appropriate spaces on the ANSWER BOOK. 2. This question paper consists of SIX 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 subquestions, e.g. between QUESTION 2.1 and QUESTION 2.2. 6. You may use a non-programmable calculator. 7. You are advised to use the attached DATA SHEETS. 8. Round off your FINAL numerical answers to a minimum of TWO decimal places. 9. Give brief motivations, discussions, etc. where required. 10. Write neatly and legibly. Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 3 DBE/2022 SC/NSC QUESTION 1: MULTIPLE-CHOICE QUESTIONS Various options are provided as possible answers to the following questions. Choose the answer and write only the letter (A–D) next to the question numbers (1.1 to 1.5) in the ANSWER BOOK, e.g. 1.6 D. 1.1 The temperature at which the solid and liquid phases of a substance are at equilibrium is known as … A vapour pressure. B boiling point. C melting point. D viscosity. (2) 1.2 Consider the diagram of a p-n junction diode below: 1 2 Which ONE of the combinations below correctly represents part 1 and part 2? 1 2 A p-type p-type B p-type n-type C n-type p-type D n-type n-type (2) 1.3 Which ONE of the following combinations is TRUE about the substance that is oxidised? ELECTRONS OXIDATION NUMBER A Gain Decreases B Loss Decreases C Gain Increases D Loss Increases (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 4 DBE/2022 SC/NSC 1.4 Which ONE of the following is an advantage of fuel (hydrogen) cell? A Hydrogen extraction is very cheap. B Hydrogen cell has minimal negative environmental impact, as it produces water only. C Hydrogen gas is safer to handle and store. D Hydrogen has a unique smell: therefore, it is easy to detect leaking pipes and containers. (2) 1.5 Which ONE of the following is CORRECT about the change in the mass of electrodes in a galvanic cell? Assume that both electrodes are solid metals. ANODE CATHODE A Decreases Increases B Decreases Decreases C Increases Increases D Increases Decreases (2) [10] Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 5 DBE/2022 SC/NSC QUESTION 2 (Start on a new page.) Consider the organic molecules in the table below and answer the questions that follow. H H H H O H A C C B H C C C H H H H H H C CH3CH2CHO D Propanone H H E C4H10 F H C C C C H H H 2.1 Compounds E and F are hydrocarbons. For these compounds, write down the LETTER that represents a hydrocarbon which is: 2.1.1 Saturated (1) 2.1.2 Unsaturated (1) 2.2 Write down the general formula for a homologous series to which compound F belongs. (2) 2.3 Draw the structural formula for the functional group of the compounds represented by the letters: 2.3.1 C (2) 2.3.2 D (2) 2.4 Consider the structural formula of compound B. 2.4.1 Give the IUPAC name of compound B. (2) 2.4.2 Draw the structural formula of the positional isomer of compound B. (2) 2.5 Compound A is a monomer that can be used to form a polymer. 2.5.1 Define the term polymer. (2) 2.5.2 Draw the structural formula of the polymer that can be formed from monomer A. (2) 2.5.3 Give the NAME of the polymer that can be formed from monomer A. (2) [18] Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 6 DBE/2022 SC/NSC QUESTION 3 (Start on a new page.) A group of learners conducted an investigation in order to find the relationship between the boiling points and the chain lengths of three alkanes. The results of the investigation are shown in the table below. COMPOUND BOILING POINT (°C) A C2H6 - 89 B C3H8 - 42 C C4H10 - 0,5 3.1 For this investigation, write down the following: 3.1.1 Investigative question (2) 3.1.2 Independent variable (1) 3.1.3 Dependent variable (1) 3.1.4 Controlled variable (1) 3.2 Before conducting the investigation, learners wrote down the following hypothesis: The weaker the intermolecular forces, the higher the boiling point. 3.2.1 Write down the NAME of the intermolecular forces referred to in the hyphothesis. (1) 3.2.2 Is their hyphothesis CORRECT or INCORRECT? Write down only CORRECT or INCORRECT. (1) 3.2.3 Explain the answer to QUESTION 3.2.2. Refer to the chain length, the strength of the intermolecular forces and boiling point. (3) 3.2.4 Use the data in the table to write down a conclusion for the investigation. (2) [12] Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 7 DBE/2022 SC/NSC QUESTION 4 (Start on a new page.) The flow diagram below shows how Compound 1, an alkene, can be converted into a haloalkane through various organic reactions. Letters A and B represent different types of reactions. H H H H A Compound 1 + H2O H C C C C H H H O H + H HF B Haloalkane 4.1 Write down the TYPE of reaction represented by: 4.1.1 A (1) 4.1.2 B (1) 4.2 Draw the structural formula of Compound 1 and also give its IUPAC name. (4) 4.3 Write down a balanced chemical reaction using structural formulae to represent reaction B. (3) 4.4 Give TWO reaction conditions for reaction A. (2) [11] Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 8 DBE/2022 SC/NSC QUESTION 5 (Start on a new page.) The diagram below represents an electrolytic cell used in the decomposition of a copper (ll) chloride solution. The electrodes used are inert. - + CuCℓ2(aq) 5.1 Define the following terms: 5.1.1 Anode (2) 5.1.2 Electrolysis (2) 5.2 Write down: 5.2.1 A balanced half-reaction that occurs at the anode (2) 5.2.2 The NAME of a half-reaction that occurs at the cathode (1) 5.3 Write down the NAME or FORMULA of: 5.3.1 An oxidising agent (1) 5.3.2 A reducing agent (1) 5.4 During the reaction in the above cell, bubbles were observed on one of the electrodes. Give the NAME of the chemical substance causing the bubbles. (1) [10] Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 9 DBE/2022 SC/NSC QUESTION 6 (Start on a new page.) 6.1 The cell notation below represents an electrochemical cell: Cu/Cu2+ (1 mol  dm-3) // Ag+ (1 mol  dm-3) / Ag 298 K/25 C 6.1.1 What energy conversion is taking place in the above cell? (2) 6.1.2 Write down TWO indicators from the cell notation that prove that the cell is operating under standard conditions. (2) 6.2 Write down a balanced half-reaction that occurs at the: 6.2.1 Cathode (2) 6.2.2 Anode (2) 6.3 Use calculations to conclude whether the reaction is SPONTANEOUS or NON-SPONTANEOUS. (5) 6.4 Give a reason for the answer to QUESTION 6.3. (1) [14] TOTAL: 75 Copyright reserved

Downloaded from hlayiso.com Technical Sciences/P2 DBE/2022 SC/NSC DATA FOR TECHNICAL SCIENCES GRADE 12 PAPER 2 GEGEWENS VIR TEGNIESE WETENSKAPPE GRAAD 12 VRAESTEL 2 TABLE 1/TABEL 1: PHYSICAL CONSTANTS/FISIESE KONSTANTES NAME/NAAM SYMBOL/SIMBOOL VALUE/WAARDE Standard pressure Standaarddruk pƟ 1,01 x 10 Pa 5 Standard temperature Standaardtemperatuur TƟ 273 K/0 °C TABLE 2/TABEL 2: FORMULAE/FORMULES Emf/Emk Ecell = Ecathode  Eanode / Esel = Ekatode  Eanode or/of Ecell = Ereduction  Eoxidation / Esel = Ereduksie  Eoksidasie or/of Ecell = Eoxidising agent  Ereducing agent / Esel = Eoksideermiddel  Ereduseermiddel Copyright reserved

Technical Sciences/P2 Downloaded from hlayiso.com DBE/2022 SC/NSC TABLE 3: THE PERIODIC TABLE OF ELEMENTS 1 2 13 14 15 16 17 18 3 4 5 6 7 8 9 10 11 12 (I) (II) (III) (IV) (V) (VI) (VII) (VIII) KEY Atomic number 1 2 2,1 H He 29 1 4 3 4 Electronegativity 1,9 Cu Symbol 5 6 7 8 9 10 1,0 Li 1,5 Be 63,5 2,0 B 2,5 C 3,0 N 3,5 O 4,0 F Ne 7 9 11 12 14 16 19 20 11 12 Approximate relative atomic mass 13 14 15 16 17 18 0,9 Na 1,2 Mg 1,5 Aℓ 1,8 Si 2,1 P 2,5 S 3,0 Cℓ Ar 23 24 27 28 31 32 35,5 40 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 0,8 K 1,0 Ca 1,3 Sc 1,5 Ti 1,6 V 1,6 Cr 1,5 Mn 1,8 Fe 1,8 Co 1,8 Ni 1,9 Cu 1,6 Zn 1,6 Ga 1,8 Ge 2,0 As 2,4 Se 2,8 Br Kr 39 40 45 48 51 52 55 56 59 59 63,5 65 70 73 75 79 80 84 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 0,8 Rb 1,0 Sr 1,2 Y 1,4 Zr Nb 1,8 Mo 1,9 Tc 2,2 Ru 2,2 Rh 2,2 Pd 1,9 Ag 1,7 Cd 1,7 In 1,8 Sn 1,9 Sb 2,1 Te 2,5 I Xe 86 88 89 91 92 96 101 103 106 108 112 115 119 122 128 127 131 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 0,7 Cs 0,9 Ba La 1,6 Hf Ta W Re Os Ir Pt Au Hg 1,8 Tℓ 1,8 Pb 1,9 Bi 2,0 Po 2,5 At Rn 133 137 139 179 181 184 186 190 192 195 197 201 204 207 209 87 88 89 0,7 Fr 0,9 Ra Ac 226 58 59 60 61 62 63 64 65 66 67 68 69 70 71 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 Copyright reserved

Downloaded from hlayiso.com Technical Sciences/P2 DBE/2022 SC/NSC TABLE 4A: STANDARD REDUCTION POTENTIALS Half-reactions Eθ (V) F2(g) + 2e ⇌ 2F + 2,87 Co + e 2+ 3+ ⇌ Co + 1,81 H2O2 + 2H +2e ⇌ + 2H2O +1,77  2+ + 1,51 MnO 4 + 8H + 5e + ⇌ Mn + 4H2O   Cℓ2(g) + 2e ⇌ 2Cℓ + 1,36 2 3+ + 1,33 Cr2O 7 + 14H + 6e + ⇌ 2Cr + 7H2O  O2(g) + 4H + 4e + ⇌ 2H2O + 1,23 MnO2+ 4H + 2e 2+ + ⇌ Mn + 2H2O + 1,23  2+ Pt + 2e ⇌ Pt + 1,20 Br2(ℓ) + 2e ⇌ 2Br + 1,07  NO 3 + 4H + 3e ⇌ + NO(g) + 2H2O + 0,96  2+ Hg + 2e ⇌ Hg(ℓ) + 0,85 Ag + e ⇌ + Ag + 0,80  + 0,80 NO 3 + 2H + e ⇌ + NO2(g) + H2O Fe + e 2+ 3+ ⇌ Fe + 0,77 O2(g) + 2H + 2e ⇌ + H2O2 + 0,68 I2 + 2e ⇌ 2I + 0,54 Cu + e ⇌ + Increasing reducing ability/ Cu + 0,52 SO2 + 4H + 4e ⇌ + Increasing oxidising ability S + 2H2O + 0,45 2H2O + O2 + 4e ⇌ 4OH + 0,40 Cu + 2e ⇌ 2+ Cu + 0,34 2 + 0,17 SO 4 + 4H + 2e + ⇌ SO2(g) + 2H2O  + 2+ Cu + e ⇌ Cu + 0,16 Sn + 2e 2+ 4+ ⇌ Sn + 0,15 S + 2H + 2e ⇌ + H2S(g) + 0,14 2H + 2e ⇌ + H2(g) 0,00 Fe + 3e ⇌  0,06 3+ Fe Pb + 2e ⇌  0,13 2+ Pb Sn + 2e ⇌  0,14 2+ Sn Ni + 2e ⇌  0,27 2+ Ni Co + 2e ⇌  0,28 2+ Co Cd + 2e ⇌  0,40 2+ Cd Cr + e 2+ ⇌  0,41 3+ Cr Fe + 2e ⇌  0,44 2+ Fe Cr + 3e ⇌  0,74 3+ Cr Zn + 2e ⇌  0,76 2+ Zn 2H2O + 2e ⇌ H2(g) + 2OH  0,83 Cr + 2e ⇌  0,91 2+ Cr Mn + 2e ⇌  1,18 2+ Mn Aℓ + 3e ⇌  1,66 3+ Aℓ Mg + 2e ⇌  2,36 2+ Mg Na + e ⇌  2,71 + Na Ca + 2e ⇌  2,87 2+ Ca Sr + 2e ⇌  2,89 2+ Sr Ba + 2e ⇌  2,90 2+ Ba + - Cs + e ⇌ Cs - 2,92  ⇌  2,93 + K +e K Li + e ⇌  3,05 + Li Copyright reserved

Downloaded from hlayiso.com Technical Sciences/P2 DBE/2022 SC/NSC TABLE 4B: STANDARD REDUCTION POTENTIALS Half-reactions/Halfreaksies E θ (V) Li + e ⇌  3,05 + Li K + e ⇌  2,93 + K Cs + e ⇌  2,92 + Cs Ba + 2e ⇌  2,90 2+ Ba Sr + 2e ⇌  2,89 2+ Sr Ca + 2e ⇌  2,87 2+ Ca Na + e ⇌  2,71 + Na Mg + 2e ⇌  2,36 2+ Mg Aℓ + 3e ⇌  1,66 3+ Aℓ Mn + 2e ⇌  1,18 2+ Mn Cr + 2e ⇌  0,91 2+ Cr 2H2O + 2e ⇌ H2(g) + 2OH  0,83 Zn + 2e ⇌  0,76 2+ Zn Cr + 3e ⇌  0,74 3+ Cr Fe + 2e ⇌  0,44 2+ Increasing oxidising ability Fe Increasing reducing ability Cr + e 2+ ⇌  0,41 3+ Cr Cd + 2e ⇌  0,40 2+ Cd Co + 2e ⇌  0,28 2+ Co Ni + 2e ⇌  0,27 2+ Ni Sn + 2e ⇌  0,14 2+ Sn Pb + 2e ⇌  0,13 2+ Pb Fe + 3e ⇌  0,06 3+ Fe 2H + 2e ⇌ + H2(g) 0,00 S + 2H + 2e ⇌ + H2S(g) + 0,14 Sn + 2e 2+ 4+ ⇌ Sn + 0,15 Cu + e + 2+ ⇌ Cu + 0,16 2 SO 4 + 4H + 2e ⇌ + SO2(g) + 2H2O + 0,17  2+ Cu + 2e ⇌ Cu + 0,34 2H2O + O2 + 4e ⇌ 4OH + 0,40 SO2 + 4H + 4e ⇌ + S + 2H2O + 0,45 Cu + e ⇌ + Cu + 0,52 I2 + 2e ⇌ 2I + 0,54 O2(g) + 2H + 2e ⇌ + H2O2 + 0,68 Fe + e 2+ 3+ ⇌ Fe + 0,77 NO 3 + 2H + e  + ⇌ NO2(g) + H2O + 0,80 Ag + e ⇌ + Ag + 0,80 Hg + 2e ⇌ 2+ Hg(ℓ) + 0,85 NO 3 + 4H + 3e + ⇌ NO(g) + 2H2O + 0,96 Br2(ℓ) + 2e ⇌ 2Br + 1,07 Pt + 2 e ⇌ 2+ Pt + 1,20 MnO2 + 4H + 2e 2+ + ⇌ Mn + 2H2O + 1,23 O2(g) + 4H + 4e ⇌ + 2H2O + 1,23 2 Cr2O 7 + 14H + 6e 3+ + ⇌ 2Cr + 7H2O + 1,33   Cℓ2(g) + 2e ⇌ 2Cℓ + 1,36   2+ MnO 4 + + 8H + 5e ⇌ Mn + 4H2O + 1,51  + H2O2 + 2H +2 e ⇌ 2H2O +1,77 Co + e 2+ 3+ ⇌ Co + 1,81 F2(g) + 2e ⇌ 2F + 2,87 Copyright reserved