Technical Sciences P2 Nov 2023 Eng_hlayiso.com_.pdf

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 12 TECHNICAL SCIENCES P2 NOVEMBER 2023 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/November 2023 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/November 2023 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 Consider the structural formula of the compound below. H H H H H C C C C H H H H H Which ONE of the following is the best description of the above compound? DESCRIPTION HOMOLOGOUS SERIES A Saturated Alkenes B Unsaturated Alkanes C Saturated Alkanes D Unsaturated Alkynes (2) 1.2 Consider the organic molecules below. 1 and 2 represent forces. H H H H H H 2 H C C C Cl H C C C Cl H H H H H H 1 Which ONE of the following is correct for forces 1 and 2? 1 2 A Interatomic Intermolecular B Hydrogen bonds London C Intermolecular Interatomic D Dipole-dipole London (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 4 DBE/November 2023 NSC 1.3 Germanium is doped with an impurity having five valence electrons. How many free electrons are available as charge carriers? A 1 B 2 C 5 D 4 (2) 1.4 An electrochemical cell is represented by the cell notation below. Zn / Zn2+ // Cu2+ / Cu Which ONE of the following is the reducing agent? A Cu B Zn2+ C Cu2+ D Zn (2) 1.5 In an electrolytic cell the anions will migrate to the … A cathode and undergo oxidation. B anode and undergo oxidation. C cathode and undergo reduction. D anode and undergo reduction. (2) [10] Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 5 DBE/November 2023 NSC QUESTION 2 (Start on a new page.) The table below represents organic molecules from different homologous series. H H A CH3CH2CH2CH3 B H C C H H H n H H H H H H H C C C C C C H Hexan-1-ol C D H H H H O H H H H O E Propanone F H C C C H H H 2.1 Define the term organic molecule. (2) 2.2 Write down the letter(s) that represent(s) the following: 2.2.1 Polymer of ethene (1) 2.2.2 Positional isomers (2) 2.2.3 Alkane (1) 2.3 Draw the STRUCTURAL FORMULA of the following compounds: 2.3.1 A (2) 2.3.2 D (2) 2.4 Compounds E and F are functional isomers. Define the term functional isomers. (2) 2.5 Write down the IUPAC name of compound F. (2) 2.6 Write down the NAME of the homologous series of compound E. (1) [15] Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 6 DBE/November 2023 NSC QUESTION 3 (Start on a new page.) The table below shows the melting points of different organic compounds. COMPOUND MELTING POINT (°C) A Propane -188 B Butane -138 C Propan-1-ol -127 3.1 Define the term melting point. (2) 3.2 Explain the difference in the melting points of compounds A and B by referring to the TYPE OF INTERMOLECULAR FORCES, MOLECULAR STRUCTURE and the STRENGTH of intermolecular forces. (3) 3.3 Learners investigated the melting points of compounds A and C. 3.3.1 Is this a fair comparison? Explain the answer. (2) 3.3.2 Formulate an investigative question. (2) 3.3.3 Identify the independent variable. (1) 3.3.4 How will the viscosity of compound A compare to that of compound C? Write down only LOWER THAN, HIGHER THAN or EQUAL TO. (1) 3.3.5 Explain the answer to QUESTION 3.3.4. (2) [13] Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 7 DBE/November 2023 NSC QUESTION 4 (Start on a new page.) Consider the following reactions involving organic compounds. H H H C C C + Reactant Y H H H Reaction 1 Propane Reaction 2 + Compound X + HBr Bromine gas 4.1 Name the TYPE of reaction represented by: 4.1.1 Reaction 1 (1) 4.1.2 Reaction 2 (1) 4.2 Write down a balanced chemical equation for reaction 1 by using MOLECULAR FORMULAE. (3) 4.3 Write down the IUPAC NAME or FORMULA of compound X. (2) 4.4 An alcohol is formed when compound X reacts with excess water. Write down ONE reaction condition other than excess water. (1) 4.5 Define EACH of the following terms: 4.5.1 Macromolecule (2) 4.5.2 Polymerisation (2) [12] Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 8 DBE/November 2023 NSC QUESTION 5 (Start on a new page.) The diagram below shows an electrolytic cell used at an electroplating company to coat an iron bar with silver. DC power source Iron bar X Electrolyte Y 5.1 Define the term electrolyte. (2) 5.2 Write down the energy conversion that takes place in this cell. (2) 5.3 Is the reaction taking place in the cell spontaneous or nonspontaneous? Give a reason for the answer. (2) 5.4 Write down the: 5.4.1 Type of reaction taking place on the iron bar (1) 5.4.2 Half-reaction taking place at electrode X (2) 5.5 Apart from enhancing the appearance, write down TWO other reasons why the iron bar is electroplated with silver. (2) 5.6 Biodiesel as a replacement for petroleum diesel is becoming more important in South Africa. State TWO advantages of using biodiesel as an alternate energy source. (2) [13] Copyright reserved Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 9 DBE/November 2023 NSC QUESTION 6 (Start on a new page.) A learner prepares an electrochemical cell by using silver and copper as electrodes. The MINIMUM voltage required to glow the bulb is 2,5 V. The cell operates under standard conditions. Cu Ag CuSO4 AgNO3 6.1 Define the term oxidation. (2) 6.2 Identify the negative electrode. (1) 6.3 In which direction will the electrons flow in the external circuit? Choose from Ag to Cu or Cu to Ag. (1) 6.4 What observation is made at the silver electrode after a while? (1) 6.5 Write down the cell notation for this cell. (3) 6.6 Use a calculation to determine whether the bulb will glow or not. (4) [12] TOTAL: 75 Copyright reserved

Downloaded from hlayiso.com Technical Sciences/P2 1 DBE/November 2023 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 p 5 1,01 x 10 Pa Standard temperature Standaardtemperatuur T 0 °C/273 K 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 Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 2 DBE/November 2023 NSC TABLE 3: THE PERIODIC TABLE OF ELEMENTS TABEL 3: DIE PERIODIEKE TABEL VAN ELEMENTE 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) Atomic number 1 KEY/SLEUTEL Atoomgetal 2 2,1 H He 1 29 4 Symbol 3 4 Electronegativity 1,9 Cu 5 6 7 8 9 10 1,0 Li 1,5 Be Elektronegatiwiteit Simbool 2,0 B 2,5 C 3,0 N 3,5 O 4,0 F Ne 63,5 7 9 11 12 14 16 19 20 11 12 13 14 15 16 17 18 0,9 Na 1,2 Mg Approximate relative atomic mass 1,5 Aℓ 1,8 Si 2,1 P 2,5 S 3,0 Cℓ Ar 23 24 Benaderde relatiewe atoommassa 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 Co 1,8 Ni 1,8 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 Rh 2,2 Pd 2,2 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 Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 3 DBE/November 2023 NSC TABLE 4A: STANDARD REDUCTION POTENTIALS TABEL 4A: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies 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 Increasing strength of oxidising agents/Toenemende sterkte van oksideermiddels Increasing strength of reducing agents/Toenemende sterkte van reduseermiddels 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  + 0,96 NO 3 + 4H + 3e ⇌ + NO(g) + 2H2O  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 ⇌ + Cu + 0,52 SO2 + 4H + 4e ⇌ + 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 Please turn over

Downloaded from hlayiso.com Technical Sciences/P2 4 DBE/November 2023 NSC TABLE 4B: STANDARD REDUCTION POTENTIALS TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies Eθ (V) Li + e ⇌  3,05 + Li K + e ⇌  2,93 + K Cs + e ⇌  2,92 + Cs Ba + 2e ⇌  2,90 2+ Ba Increasing strength of oxidising agents/Toenemende sterkte van oksideermiddels Increasing strength of reducing agents/Toenemende sterkte van reduseermiddels 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+ Fe 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  2+ 3+ Fe + e ⇌ 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 3+ Cr2O 7 + 14H + 6e + ⇌ 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