Technical Sciences Grade 12 P2 Eastern Cape June 2024 QP

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 12 JUNE 2024 TECHNICAL SCIENCES: CHEMISTRY P2 MARKS: 75 TIME: 1½ hours This question paper consists of 15 pages, including 4 data sheets. Hosted by www.ecexams.co.za

Downloaded from hlayiso.com 2 TECHNICAL SCIENCES P2 (EC/JUNE 2024) INSTRUCTIONS AND INFORMATION 1. Write your FULL NAME and SURNAME in the appropriate spaces in the ANSWER BOOK. 2. This question paper consists of SIX questions. Answer ALL the questions. 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 sub-questions, for example 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. You may use appropriate mathematical instruments. 10. Show ALL formulae and substitutions in ALL calculations. 11. Give brief motivations, discussions et cetera where required. 12. Write neatly and legibly. Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/JUNE 2024) TECHNICAL SCIENCES P2 3 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, for example 1.6 E. 1.1 The process of adding impurities to intrinsic semiconductors is called a(n) ... A intrinsic semiconductor. B pure semiconductor. C doping. D purification. (2) 1.2 Consider the following structural formulae for compounds A and B. These compounds have the same … and differ with … A molecular formulae; positional isomers. B molecular formulae; position of the functional group. C molecules; positions. D position of the functional group; structural formulae. (2) Copyright reserved Please turn over

Downloaded from hlayiso.com 4 TECHNICAL SCIENCES P2 (EC/JUNE 2024) 1.3 Study the organic reaction below and answer the following question. CH4 + Y CO2 + H2O Which ONE of the following does Y represent, and which is the correct reaction condition for products to form? A H20 and excess water B O2 and mild heat C H2 and heat D O2 and excess oxygen (2) 1.4 Which of the following sets is the correct for an N-type semiconductor? 1 2 3 A donor level The extra electron is free to Not negatively charged move B acceptor band Electrons in the valence The absence of an band move from hole to electron creates the hole effect of a positive charge C donor level Electrons in the valence Not negatively charged band move from hole to hole D acceptor band The extra electron is free to The absence of an move electron creates the effect of a positive charge (2) 1.5 P-n junction (i) In doping, a pure element is added to a semiconductor to improve the conductivity of the semiconductor. (ii) In doping, a catalyst is added to a semiconductor to improve the conductivity of the semiconductor. (iii) The n-region becomes positively charged because it has lost some electrons. (iv) There is potential difference between the two sides of the diode. (v) Electrons (few) gain enough thermal energy to cross the energy gap (from the valence band) to the conduction band. Which ONE of the following combinations below is CORRECT for a p-n junction? A (i) and (ii) B (ii) and (iii) C (i) and (iv) D (iii) and (iv) (2) [10] Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/JUNE 2024) TECHNICAL SCIENCES P2 5 QUESTION 2 (Start on a new page.) Consider the organic compounds represented by the letters A to H below and answer the questions that follow. A Hex-2-ene E 2-methylpropan-2-ol B F Ethylethanoate C G D H C5H12 2.1 Define the term functional group. (2) 2.2 Write down the letter(s) that represents the following: 2.2.1 A tertiary alcohol (1) 2.2.2 Unsaturated hydrocarbons (1) 2.2.3 An ester (1) 2.2.4 Hydrocarbons (1) 2.2.5 Positional isomers (1) Copyright reserved Please turn over

Downloaded from hlayiso.com 6 TECHNICAL SCIENCES P2 (EC/JUNE 2024) 2.3 Write down the IUPAC name of the following: 2.3.1 D (1) 2.3.2 B (1) 2.3.3 G (1) 2.4 Write down the: 2.4.1 STRUCTURAL formula of compound F (2) 2.4.2 STRUCTURAL formula for the functional group of compound C (1) 2.4.3 MOLECULAR formula of compound A (1) 2.4.4 The name of the functional group of compound B (1) 2.4.5 STRUCTURAL formula of compound E (2) [17] Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/JUNE 2024) TECHNICAL SCIENCES P2 7 QUESTION 3 (Start on a new page.) Students were observing the vapour pressure of three (3) organic compounds from a homologous series with a general formula CnH2n+2, represented by X, Y and Z. The number of carbon atoms of these organic compounds ranges between 3 carbon atoms and 5 carbon atoms. Their results were graphed as follows: COMPOUND VAPOUR PRESSURE (kPa) MOLECULAR MASS (g.mol-1) X 215 58 Y 202 73 Z 156 86 3.1 Define the term vapour pressure. (2) 3.2 Use the table above to draw a sketch graph of vapour pressure versus molecular mass. (3) 3.3 What hypothesis can be deduced from the graph? (1) 3.4 Give the industrial use of these organic compounds. (1) 3.5 Explain the difference in the vapour pressure of compound Y and Z. Refer to the MOLECULAR MASS, STRENGTH OF INTERMOLECULAR FORCES and THE ENERGY NEEDED. (3) 3.6 Which compound will have the …? (Write only X, Y or Z.) 3.6.1 highest viscosity (1) 3.6.2 lowest melting point (1) 3.6.3 highest boiling point (1) [13] Copyright reserved Please turn over

Downloaded from hlayiso.com 8 TECHNICAL SCIENCES P2 (EC/JUNE 2024) QUESTION 4 (Start on a new page.) The table below shows the boiling points of four organic compounds, represented by the letters I to L, of comparable molecular mass. COMPOUND FORMULA BOILING POINT (°C) A I CH3OH 80 B J CH2Cℓ2 40,1 C K CHCℓ3 61,8 D L CCℓ4 76,6 4.1 Define the term boiling point. (2) 4.2 In which homologous series does compound K in the table belong? (1) 4.3 Name the intermolecular forces in compound J. (1) 4.4 What trend can be observed from compound J to compound L, in the table? (1) 4.5 An investigation was conducted on the boiling points of compounds I and L. 4.5.1 Provide the IUPAC name of compound L. (1) 4.5.2 The comparison of I and L is a fair comparison. Give a reason why this is a true statement. (1) 4.5.3 Explain how the vapour pressure of compound I will compare to that of compound L. (2) [9] Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/JUNE 2024) TECHNICAL SCIENCES P2 9 QUESTION 5 (Start on a new page.) Alcohol H can be converted to many other compounds and be a product of other reactions. As such alcohol H was used to form an organic compound called propyl butanoate. Study the table below and answer the questions that follow. REACTION NUMBER ORGANIC REACTION REACTION 1 Alkene + R Alcohol H REACTION 2 Alkene + S Alkane W REACTION 3 Alcohol H + Br2 Haloalkane + V REACTION 4 Haloalkane + R Alcohol H + T REACTION 5 Alkane W + Y Z + H2O 5.1 Are the intermolecular forces in propyl butanoate WEAKER or STRONGER than those in alcohol H? Write only WEAKER or STRONGER. (1) 5.2 Identify alcohol H. (1) 5.3 Write down the type of reaction represented by the following reactions: 5.3.1 Reaction 1 (1) 5.3.2 Reaction 3 (1) 5.3.3 Reaction 5 (1) 5.4 For Reaction 2: 5.4.1 Write down the STRUCTURAL FORMULA for the alkene. (2) 5.4.2 Is compound S, ORGANIC or INORGANIC? (1) 5.4.3 Explain the answer to QUESTION 5.4.2 above. (1) Copyright reserved Please turn over

Downloaded from hlayiso.com 10 TECHNICAL SCIENCES P2 (EC/JUNE 2024) 5.5 For Reaction 1, write down: 5.5.1 The balanced chemical equation using STRUCTURAL FORMULAE (3) 5.5.2 One reaction condition (1) 5.6 For Reaction 5, write down: 5.6.1 The STRUCTURAL FORMULA for alkane W (2) 5.6.2 NAME for compound Y (1) 5.6.3 FORMULA for compound Z (1) [17] Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/JUNE 2024) TECHNICAL SCIENCES P2 11 QUESTION 6 (Start on a new page.) Study the diagram of a semiconductor below and answer questions that follow. Note the following about semiconductors: • Some semiconductors are formed by adding impurities to them and some formed at high temperatures where the atoms vibrate. • Semiconductors are used in the manufacture of electronic devices such as diodes, transistors, and integrated circuits. 6.1 Which element represents a dopant in the diagram? Write only Si or B. (1) 6.2 How many valence electrons does this dopant have? (1) 6.3 What does A in the diagram above, represent? (1) 6.4 Define a semiconductor. (2) 6.5 Briefly explain what will happen if the semiconductor above is connected across the terminals of a cell. (2) 6.6 What is the purpose of doping? (1) 6.7 Identify the type of a semiconductor represented by the diagram above. (1) [9] TOTAL: 75 Copyright reserved Please turn over

Downloaded from hlayiso.com 12 TECHNICAL SCIENCES P2 (EC/JUNE 2024) NATIONAL SENIOR CERTIFICATE NASIONALE SENIOR SERTIFIKAAT DATA FOR TECHNICAL SCIENCES GRADE 12 PAPER 2 (CHEMISTRY) GEGEWENS VIR TEGNIESE WETENSKAPPE GRAAD 12 VRAESTEL 2 (CHEMIE) TABLE 1: PHYSICAL CONSTANTS/TABEL 1: FISIESE KONSTANTES NAAM/NAME SIMBOOL/SYMBOL WAARDE/VALUE Avogadro se konstante NA 6,02 × 1023 mol-1 Avogadro’s constant Molêre gaskonstante R 8,31 J.K-1.mol-1 Molar gas constant Standaarddruk p 1,013 × 105 Pa Standard pressure Molêre gasvolume teen STD Vm 22,4 dm3∙mol-1 Molar gas volume at STP Standaardtemperatuur Standard temperature Tθ 273 K TABLE 2: FORMULAE/TABEL 2: FORMULES m n m n = M or/of c = V or/of c = MV pH= -log[H3O+] Kw = [H3O+][OH-] = 1x10-14 N ca Va na at /by 298K n= N or/of = A cb Vb nb V n= V m Eθcell = Eθcathode – Eθanode / Eθsel = Eθkatode – Eθanode Eθcell = Eθreduction – Eθoxidation / Eθsel = Eθreduksie – Eθoksidasie Eθcell = Eθoxidising agent – Eθreducing agent / Eθsel = Eθoksideermiddel – Eθreduseermiddel Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/JUNE 2024) TECHNICAL SCIENCES P2 13 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 15 16 17 18 (I) (II) Atoomgetal (III) (IV) (V) (VI) (VII) (VIII) KEY/ SLEUTEL Atomic number 1 2 2,1 H He 1 29 4 3 4 Elektronegatiwiteit Simbool 5 6 7 8 9 10 1,0 Li 1,5 Be Electronegativity 1,9 Cu Symbol 2,0 B 2,5 C 3,0 N 3,5 O 4,0 F Ne 7 9 63,5 11 12 14 16 19 20 11 12 13 14 15 16 17 18 Benaderde relatiewe atoommassa 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 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 1,5Ti 1,6 V 1,6 Cr 1,5 Mn 1,8 Fe 1,8 Co 1,8Ni 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 1,4Zr 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 1,6Hf 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 14 TECHNICAL SCIENCES P2 (EC/JUNE 2024) TABLE 4A: STANDARD REDUCTION POTENTIALS TABEL 4A: STANDAARD REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E θ (V) F2(g) + 2e− ⇌ 2F− + 2,87 Co 3+ +e − ⇌ Co2+ + 1,81 H2O2 + 2H+ +2e− ⇌ 2H2O +1,77 − MnO 4 + 8H+ + 5e− ⇌ Mn2+ + 4H2O + 1,51 Cℓ2(g) + 2e− ⇌ 2Cℓ − + 1,36 2− Cr2O 7 + 14H+ + 6e− ⇌ 2Cr3+ + 7H2O + 1,33 O2(g) + 4H+ + 4e− ⇌ 2H2O + 1,23 MnO2 + 4H+ + 2e− ⇌ Mn2+ + 2H2O + 1,23 Pt2+ + 2e− ⇌ Pt + 1,20 Br2(ℓ) + 2e − ⇌ 2Br − + 1,07 − NO 3 + 4H+ + 3e− ⇌ NO(g) + 2H2O + 0,96 Increasing reducing ability/Toenemende reduserende vermoë Increasing oxidising ability/Toenemende oksiderende vermoë Hg 2+ + 2e − ⇌ Hg(ℓ) + 0,85 Ag+ + e− ⇌ Ag + 0,80 − NO 3 + 2H+ + e− ⇌ NO2(g) + H2O + 0,80 Fe3+ + e− ⇌ Fe2+ + 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 Cu2+ + 2e− ⇌ Cu + 0,34 2− SO 4 + 4H+ + 2e− ⇌ SO2(g) + 2H2O + 0,17 Cu2+ + e− ⇌ Cu+ + 0,16 Sn 4+ + 2e − ⇌ Sn2+ + 0,15 S + 2H+ + 2e− ⇌ H2S(g) + 0,14 2H+ + 2e− ⇌ H2(g) 0,00 Fe 3+ + 3e − ⇌ Fe − 0,06 Pb2+ + 2e− ⇌ Pb − 0,13 Sn2+ + 2e− ⇌ Sn − 0,14 Ni2+ + 2e− ⇌ Ni − 0,27 Co 2+ + 2e − ⇌ Co − 0,28 Cd2+ + 2e− ⇌ Cd − 0,40 Cr3+ + e− ⇌ Cr2+ − 0,41 Fe 2+ + 2e − ⇌ Fe − 0,44 Cr3+ + 3e− ⇌ Cr − 0,74 Zn2+ + 2e− ⇌ Zn − 0,76 2H2O + 2e− ⇌ H2(g) + 2OH− − 0,83 Cr 2+ + 2e − ⇌ Cr − 0,91 Mn2+ + 2e− ⇌ Mn − 1,18 Aℓ3+ + 3e− ⇌ Aℓ − 1,66 Mg2+ + 2e− ⇌ Mg − 2,36 + Na + e − ⇌ Na − 2,71 Ca2+ + 2e− ⇌ Ca − 2,87 Sr2+ + 2e− ⇌ Sr − 2,89 Ba2+ + 2e− ⇌ Ba − 2,90 + Cs + e - ⇌ Cs - 2,92 K+ + e− ⇌ K − 2,93 Li+ + e− ⇌ Li − 3,05 Copyright reserved Please turn over

Downloaded from hlayiso.com (EC/JUNE 2024) TECHNICAL SCIENCES P2 15 TABLE 4B: STANDARD REDUCTION POTENTIALS TABEL 4B: STANDAARD REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E θ (V) Li+ + e− ⇌ Li − 3,05 K+ + e− ⇌ K − 2,93 Cs+ + e− ⇌ Cs − 2,92 Ba2+ + 2e− ⇌ Ba − 2,90 Sr2+ + 2e− ⇌ Sr − 2,89 Ca2+ + 2e− ⇌ Ca − 2,87 + Na + e − ⇌ Na − 2,71 Mg2+ + 2e− ⇌ Mg − 2,36 Aℓ3+ + 3e− ⇌ Aℓ − 1,66 Mn2+ + 2e− ⇌ Mn − 1,18 Increasing reducing ability/Toenemende reduserende vermoë Cr2+ + 2e− ⇌ Cr − 0,91 2H2O + 2e− ⇌ H2(g) + 2OH− − 0,83 Increasing oxidising ability/Toenemende oksiderende vermoë Zn2+ + 2e− ⇌ Zn − 0,76 3+ Cr + 3e − ⇌ Cr − 0,74 Fe2+ + 2e− ⇌ Fe − 0,44 Cr3+ + e− ⇌ Cr2+ − 0,41 Cd2+ + 2e− ⇌ Cd − 0,40 Co2+ + 2e− ⇌ Co − 0,28 Ni2+ + 2e− ⇌ Ni − 0,27 2+ Sn + 2e − ⇌ Sn − 0,14 Pb2+ + 2e− ⇌ Pb − 0,13 Fe3+ + 3e− ⇌ Fe − 0,06 2H+ + 2e− ⇌ H2(g) 0,00 S + 2H+ + 2e− ⇌ H2S(g) + 0,14 4+ Sn + 2e − ⇌ Sn 2+ + 0,15 Cu2+ + e− ⇌ Cu+ + 0,16 2− SO 4 + 4H+ + 2e− ⇌ SO2(g) + 2H2O + 0,17 Cu2+ + 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 3+ Fe + e − ⇌ Fe 2+ + 0,77 − NO 3 + 2H+ + e− ⇌ NO2(g) + H2O + 0,80 + Ag + e − ⇌ Ag + 0,80 Hg2+ + 2e− ⇌ Hg(ℓ) + 0,85 − NO 3 + 4H+ + 3e− ⇌ NO(g) + 2H2O + 0,96 Br2(ℓ) + 2e − ⇌ 2Br − + 1,07 Pt2+ + 2 e− ⇌ Pt + 1,20 MnO2 + 4H+ + 2e− ⇌ Mn2+ + 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 − MnO 4 + 8H+ + 5e− ⇌ Mn2+ + 4H2O + 1,51 H2O2 + 2H+ +2 e− ⇌ 2H2O +1,77 Co3+ + e− ⇌ Co2+ + 1,81 F2(g) + 2e− ⇌ 2F− + 2,87 Copyright reserved Please turn over