Technical Sciences P2 (English) 2022 QP hlayiso.com

Downloaded from hlayiso.com PREPARATORY EXAMINATION 2022 11102 TECHNICAL SCIENCES PAPER 2 TIME: 1½ hours MARKS: 75 10 pages + 4 information sheets P.T.O.

Downloaded from hlayiso.com TECHNICAL SCIENCES 2 (Paper 2) 11102/22 INSTRUCTIONS AND INFORMATION 1. This question paper consists of SIX questions. Answer ALL the questions in the ANSWER BOOK. 2. Start EACH question on a NEW page in the ANSWER BOOK. 3. Number the answers correctly according to the numbering system used in this question paper. 4. Leave ONE line between two sub-questions, e.g. between QUESTION 2.1 and QUESTION 2.2. 5. You may use a non-programmable calculator. 6. You are advised to use the attached DATA SHEETS. 7. Round-off your FINAL numerical answers to a minimum of TWO decimal places. 8. Give brief motivations, discussions, etc., where required. 9. Write neatly and legibly. P.T.O.

Downloaded from hlayiso.com TECHNICAL SCIENCES 3 (Paper 2) 11102/22 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 1.6) in the ANSWER BOOK, e.g. 1.7 D. 1.1 Which of the following compounds represents the first member of the ketones? A HCHO B CH3OH C H3COCH3 D CH3CH2COOH (2) 1.2 Which of the following compounds is saturated? A C4H10 B C5H10 C C5H9OH D C6H10 (2) 1.3 Consider the compound with molecular formula of C5H11OH. To which homologous series does this compound belong? A Aldehydes B Ketones C Esters D Alcohols (2) 1.4 Methyl ethanoate is prepared by the reaction between ... A ethanoic acid and ethanol. B ethanoic acid and methanol. C methanoic acid and methanol. D methanoic acid and ethanol. (2) P.T.O.

Downloaded from hlayiso.com TECHNICAL SCIENCES 4 (Paper 2) 11102/22 1.5 Which of the following definitions does NOT describe electrolysis? A The dissolution of a substance using an electrical current B The chemical process where electrical energy is converted to chemical energy C The use of electrical energy to cause a chemical change D The use of chemical energy to cause an electrical change (2) 1.6 Choose the correct comparison between an electrolytic cell and a galvanic cell. A A galvanic cell is an electrochemical cell where electrical energy is converted into chemical energy and an electrolytic cell is where chemical energy is converted into electrical energy. B An electrolytic cell is an electrochemical cell where electrical energy is converted into chemical energy and a galvanic cell is where chemical energy is converted into electrical energy. C A galvanic cell is a non-spontaneous cell, whereas an electrolytic cell is a spontaneous cell. D Both cells are electrochemical cells that convert electrical energy into chemical energy. (2) [12] P.T.O.

Downloaded from hlayiso.com TECHNICAL SCIENCES 5 (Paper 2) 11102/22 QUESTION 2 (Start on a new page.) Letters A to F in the table below represent SIX organic molecules. A C4H8 B Ethane C Bromine D Ethanoic acid E F 2.1 Define a functional group. (2) 2.2 Give the IUPAC name of compound E. (2) 2.3 From the list above choose a substance that is used in the laboratory for the preparation of E. Write down ONLY the letter. (1) 2.4 Give the name or formula of the catalyst that is needed for the reaction referred to in QUESTION 2.3. (1) 2.5 Write down the structural formulae of THREE isomers of substance A. Write down the IUPAC name under each isomer. (6) 2.6 Write down the structural formula of compound D. (2) 2.7 Define an unsaturated hydrocarbon. (2) 2.8 Identify an unsaturated hydrocarbon from the table above. Write down ONLY the letter of the correct answer. (1) [17] P.T.O.

Downloaded from hlayiso.com TECHNICAL SCIENCES 6 (Paper 2) 11102/22 QUESTION 3 (Start on a new page.) Knowledge of the boiling points may be used to identify chemical compounds. The boiling points of four organic compounds, represented by the letters A, B, C and D are shown in the table below. Compound Boiling Point ˚C A Propane -42 B Pentane 36 C 2-methylbutane 27,8 D Pentan-1-ol 137 3.1 Define the term boiling point. (2) 3.2 Between A and B, which has the higher vapour pressure? (1) 3.3 An unknown straight chain alkane has a boiling point of -0,5 °C. Use the information in the table above to identify this alkane and write down its IUPAC name. (2) 3.4 B and C are structural isomers. 3.41 Define the term structural isomer. (2) 3.4.2 Explain why B has a higher boiling point than C. Refer to chain length/ branch, intermolecular forces and energy in your explanation. (3) [10] P.T.O.

Downloaded from hlayiso.com TECHNICAL SCIENCES 7 (Paper 2) 11102/22 QUESTION 4 (Start on a new page.) Pentane is one of the important hydrocarbons used in the synthesis of petroleum for vehicles. 4.1 Write down the balanced chemical reaction of the combustion of pentane in excess oxygen. (3) 4.2 The flow diagram below shows how pentane can be converted to several other organic compounds. Study the reactions (A to E) and answer the questions that follow. But-2-ene Reaction C Butane Haloalkane Alcohol Reaction E 4.2.1 Which reaction is a representation of hydrohalogenation? (1) 4.2.2 From the flow diagram above, write a balanced chemical equation for reaction B to show the formation of the major product. (3) 4.2.3 Write a suitable name given to reaction C in the flow diagram above. (1) 4.2.4 Which catalyst may be used in reaction C above? (1) 4.3 Reaction E results in the formation of alcohol as one of the products. 4.3.1 What are the TWO reaction conditions for reaction E? (2) 4.3.2 Write down the IUPAC name of the alcohol formed in the reaction E above. (1) [12] P.T.O.

Downloaded from hlayiso.com TECHNICAL SCIENCES 8 (Paper 2) 11102/22 QUESTION 5 (Start on a new page.) The electrochemical cell below is used to decompose copper(II)chloride. C B A D Use the above diagram to answer the following questions. 5.1 What type of electrochemical cell is represented in the diagram above? (1) 5.2 Identify the following electrodes as anode or cathode: 5.2.1 Electrode A (1) 5.2.2 Electrode B (1) 5.3 What type of electrochemical cell does component C represent? (1) 5.4 To which electrode will the copper ions be attracted? (1) 5.5 Write down the oxidation half-reaction for the above electrochemical cell. (2) 5.6 Write down the reduction half-reaction for the above electrochemical cell. (2) 5.7 Write down the net balanced chemical equation for the reaction in the electrochemical cell above. (3) 5.8 State ONE precautionary measure that must be taken into consideration while the cell is in operation. (1) P.T.O.

Downloaded from hlayiso.com TECHNICAL SCIENCES 9 (Paper 2) 11102/22 5.9 What energy conversion takes place in this type of cell? (2) 5.10 Two Grade 12 learners want to use the cell to coat copper with a layer of gold. Name the TWO electrodes that the learners can use to replace the graphite electrodes in this cell. (2) 5.11 Give a suitable name for the process referred to in QUESTION 5.10 above. (1) 5.12 At which electrode (cathode or anode) will they connect gold as an electrode? (1) 5.13 One of the observations is that the concentration of ions in the electrolyte used remains constant. Provide a suitable explanation for this observation. (1) [20] P.T.O.

Downloaded from hlayiso.com TECHNICAL SCIENCES 10 (Paper 2) 11102/22 QUESTION 6 (Start on a new page.) Fossil fuel is a non-renewable source of energy which is being exhausted. This means that new sources of energy must be developed, which is called alternative energy, for example, environmentally-friendly hydrogen fuel cells. Use the following diagram of a hydrogen fuel cell to answer the questions that follow. Fuel in Air in O2 and other gases Unused Excess gases fuel out Anode Cathode Electrolyte 6.1 Name the TWO reactants used in the hydrogen fuel cell. (2) 6.2 Why is a catalyst used in this hydrogen fuel cell? (1) 6.3 Name ONE advantage of hydrogen fuel cells over batteries, gasoline and diesel engines. (1) [4] TOTAL: 75 END

Downloaded from hlayiso.com TECHNICAL SCIENCES 11 (Paper 2) 11102/22 DATA FOR TECHNICAL SCIENCES GRADE 12/ GEGEWENS VIR TEGNIESE WETENSKAPPE GRAAD 12 PAPER/VRAESTEL 2 TABLE/TABEL 1 PHYSICAL CONSTANTS/FISIESE KONSTANTES CONSTANT/KONSTANTE SYMBOL/SIMBOOL VALUE/WAARDE Planck's constant Planck se konstante h 6,63 x 10-34 J.s Speed of light Spoed van lig c 3 x 108 m.s-1 TABLE/TABEL 2 WAVES, SOUND AND LIGHT/GOLWE, KLANK EN LIG Speed/Spoed c=fλ Energy/Energie E = hf or/of hc E= λ TABLE/TABEL 3 ELECTROCHEMISTRY/ELEKTROCHEMIE Emf/Emk Eθcell = Eθcathode − Eθanode / E θsel = Ekatode θ − E θanode or/of E θcell = Ereduction θ − Eθoxidation / Eθsel = Ereduksie θ − E θoksidasie or/of E θcell = E θoxidising agent − E θreducing agent / E sel = E oksideermi ddel − E reduseermi ddel θ θ θ

Downloaded from hlayiso.com TECHNICAL SCIENCES 12 (Paper 2) 11102/22 TABLE 4A: STANDARD REDUCTION POTENTIALS/ TABEL 4A: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies Eθ (V) F2(g) + 2e− ⇌ 2F− + 2,87 Co3+ + 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 Hg2+ + 2e− ⇌ Hg(ℓ) + 0,85 Increasing oxidising ability/Toenemende oksiderende vermoë Ag+ + e− ⇌ Ag + 0,80 Increasing reducing ability/Toenemende reduserende vermoë − 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 Sn4+ + 2e− ⇌ Sn2+ + 0,15 S + 2H+ + 2e− ⇌ H2S(g) + 0,14 2H+ + 2e− ⇌ H2(g) 0,00 Fe3+ + 3e− ⇌ Fe − 0,06 Pb2+ + 2e− ⇌ Pb − 0,13 Sn2+ + 2e− ⇌ Sn − 0,14 Ni2+ + 2e− ⇌ Ni − 0,27 Co2+ + 2e− ⇌ Co − 0,28 Cd2+ + 2e− ⇌ Cd − 0,40 Cr3+ + e− ⇌ Cr2+ − 0,41 Fe2+ + 2e− ⇌ Fe − 0,44 Cr3+ + 3e− ⇌ Cr − 0,74 Zn2+ + 2e− ⇌ Zn − 0,76 2H2O + 2e− ⇌ H2(g) + 2OH− − 0,83 Cr2+ + 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

Downloaded from hlayiso.com TECHNICAL SCIENCES 13 (Paper 2) 11102/22 TABLE 4B: STANDARD REDUCTION POTENTIALS/ TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE Eθ (V) Half-reactions/Halfreaksies Li+ + e− ⇌ Li − 3,05 K+ + e− ⇌ K − 2,93 Cs+ + e− ⇌ Cs − 2,92 Ba2+ + 2e− ⇌ Ba − 2,90 Increasing reducing ability/Toenemende reduserende vermoë Sr2+ + 2e− − 2,89 Increasing oxidising ability/Toenemende oksiderende vermoë ⇌ Sr 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 Cr2+ + 2e− ⇌ Cr − 0,91 2H2O + 2e− ⇌ H2(g) + 2OH− − 0,83 Zn2+ + 2e− ⇌ Zn − 0,76 Cr3+ + 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 Sn2+ + 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 Sn4+ + 2e− ⇌ Sn2+ + 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− ⇌ H2 O 2 + 0,68 Fe3+ + e− ⇌ Fe2+ + 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− ⇌ 2Cr3+ + 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

Downloaded from hlayiso.com TECHNICAL SCIENCES 14 (Paper 2) 11102/22 TABLE 5: THE PERIODIC TABLE OF ELEMENTS/TABEL 5: 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) (III) (IV) (V) (VI) (VII) (VIII) Atomic number/ KEY/SLEUTEL 1 Atoomgetal 2 2,1 H He 1 29 4 3 4 Electronegativity/ 1,9 Cu Symbol/ 5 6 7 8 9 10 1,0 Li 1,5 Be Elektronegatiwiteit 63,5 Simbool 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 13 14 15 16 17 18 Approximate relative atomic mass/ 0,9 Na 1,2 Mg Benaderde relatiewe atoommassa 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 58 59 60 61 62 63 64 65 66 67 68 69 70 71 226 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