Physical Sciences Grade 12 P2 November 2024 NSC QP (Eng)

Confidential NATIONAL SENIOR CERTIFICATE GRADE 12 PHYSICAL SCIENCES: CHEMISTRY (P2) NOVEMBER 2024 MARKS: 150 TIME: 3 hours This question paper consists of 17 pages and 4 data sheets. Copyright reserved Please turn over

Physical Sciences/P2 2 DBE/November 2024 NSC Confidential 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 NINE 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. Show ALL formulae and substitutions in ALL calculations. 8. Round off your FINAL numerical answers to a minimum of TWO decimal places. 9. Give brief motivations, discussions, etc. where required. 10. You are advised to use the attached DATA SHEETS. 11. Write neatly and legibly. Copyright reserved Please turn over

Physical Sciences/P2 3 DBE/November 2024 NSC Confidential QUESTION 1: MULTIPLE-CHOICE QUESTIONS Various options are provided as possible answers to the following questions. Each question has only ONE correct answer. Choose the answer and write only the letter (A–D) next to the question numbers (1.1 to 1.10) in the ANSWER BOOK, e.g. 1.11 E. Nov 1.1 Which ONE of the following compounds has hydrogen bonds between its molecules? A CH3CH2CHO B CH3COOCH3 C CH3CH2CH2OH D CH3COCH3 (2) 1.2 Which ONE of the following is a CORRECT GENERAL FORMULA for the carboxylic acids? A CnH2n+1O2 B CnH2nO2n C CnH2nO2 D CnHnO2 (2) 1.3 Study the reactions below. H2SO4 Reaction 1: CH3CH2CHOHCH3 conc. Compound P (major product) + H2O hydrogenation Reaction 2: Compound P Compound Q Which ONE of the following combinations is the CORRECT IUPAC names of compounds P and Q? COMPOUND P COMPOUND Q A But-1-ene Butane B But-2-ene Butane C But-1-ene Butan-2-ol D But-2-ene Butan-2-ol (2) Copyright reserved Please turn over

Physical Sciences/P2 4 DBE/November 2024 NSC Confidential 1.4 The potential energy diagram below is for the following hypothetical chemical reaction: X + Y ⇌ Z Potential energy Course of reaction Which ONE of the following combinations of values for the heat of the reaction and the activation energies can be obtained for this reaction? ∆H(forward) EA(forward) EA(reverse) (kJ·mol–1) (kJ·mol–1) (kJ·mol–1) A -400 300 100 B -200 300 100 C +400 100 300 D -200 100 300 (2) 1.5 Initially, an equal number of moles of hydrogen gas, H2(g), and iodine gas, I2(g), are mixed in a closed container. The reaction reaches equilibrium at a constant temperature according to the balanced equation. H2(g) + I2(g) ⇌ 2HI(g) Which ONE of the following is ALWAYS TRUE at equilibrium? A [H2] = [I2] B [HI] = [I2] C [HI] = 2[H2] D [H2] = [I2] = [HI] (2) Copyright reserved Please turn over

Physical Sciences/P2 5 DBE/November 2024 NSC Confidential 1.6 Consider the following reaction at equilibrium: 2SO2(g) + O2(g) ⇌ 2SO3(g) ΔH = −188 kJ·mol–1 Which ONE of the changes to the reaction conditions below will increase the yield of SO3(g)? A The addition of O2(g) B The addition of a catalyst C An increase in temperature D An increase in the volume of the container at a constant temperature (2) 1.7 The table below shows the ionisation constants, Ka, for two acids at 25 °C. ACID Ka Butanoic acid 1,5 x 10-5 Ethanoic acid 1,8 x 10-5 Consider the following statements for these two acids when they have equal concentration at 25 °C: (i) Both are weak acids. (ii) Butanoic acid is a stronger acid than ethanoic acid. (iii) The butanoic acid solution has a lower concentration of hydronium ion, H3O+(aq), than the ethanoic acid solution. Which of the above statements are TRUE? A (i) and (ii) only B (i) and (iii) only C (ii) and (iii) only D (i), (ii) and (iii) (2) 1.8 Which ONE of the following pairs of acids and bases, all of the same concentration, react to give the highest pH at the equivalence point in a titration at 25 °C? A HCℓ and NH3 B HCℓ and NaOH C HNO3 and KOH D CH3COOH and NaOH (2) Copyright reserved Please turn over

Physical Sciences/P2 6 DBE/November 2024 NSC Confidential 1.9 A standard galvanic cell is set up, as shown below. V Cd Ag Cd2+(aq) Ag+(aq) Which ONE of the following combinations of the metal used as cathode and the electron flow direction is CORRECT? METAL USED AS ELECTRON FLOW CATHODE DIRECTION A Cd Cd to Ag B Ag Cd to Ag C Cd Ag to Cd D Ag Ag to Cd (2) 1.10 An electrolytic cell is set up to electroplate an iron rod with nickel, as shown in the diagram below. Consider the following statements: (i) The iron rod is the negative electrode. (ii) The metal ions in the solution undergo reduction. (iii) The anode is pure nickel. Which of the above statements are TRUE? A (i) and (ii) only B (i) and (iii) only C (ii) and (iii) only D (i), (ii) and (iii) (2) [20] Copyright reserved Please turn over

Physical Sciences/P2 7 DBE/November 2024 NSC Confidential QUESTION 2 (Start on a new page.) The letters A to H in the table below represent organic compounds. H H C H H C H H H H O H Br H H A H C C C C H B H C C C C C H H H H H Br H H H C H H C Butanone D C4H10O E CH3C(CH3)2CCCH3 F CH3COO(CH2)2CH3 G C4H8O2 H CH3C(CH3)2CH2CH3 2.1 Write down the LETTER that represents EACH of the following: 2.1.1 An alcohol (1) 2.1.2 A compound with a formyl group (1) 2.1.3 An unsaturated compound (1) 2.2 Write down the IUPAC name of compound: 2.2.1 B (3) 2.2.2 E (3) 2.3 Two different compounds in the above table are functional isomers. 2.3.1 Define the term functional isomer. (2) 2.3.2 Write down the LETTERS that represent these functional isomers. (1) Copyright reserved Please turn over

Physical Sciences/P2 8 DBE/November 2024 NSC Confidential 2.4 Compound F is formed when a carboxylic acid reacts with another organic compound, X, in the presence of a catalyst. Write down the: 2.4.1 NAME or FORMULA of the catalyst (1) 2.4.2 Type of reaction (1) 2.4.3 STRUCTURAL FORMULA of compound F (2) 2.4.4 IUPAC name of compound X (2) [18] QUESTION 3 (Start on a new page.) The vapour pressures of different organic compounds are determined at 20 °C. The vapour pressures of compounds A, B and C are NOT shown in the table. MOLAR VAPOUR COMPOUND IUPAC NAME MASS PRESSURE (kPa) (g·mol-1) AT 20 °C A Pentane 72 B 2-methylbutane 72 C 2,2-dimethylpropane 72 D Propanoic acid 74 0,32 E Butanal 72 12,2 3.1 Define the term vapour pressure. (2) 3.2 The vapour pressures of compounds A, B and C are given in random order below. 79 kPa 146 kPa 58 kPa 3.2.1 Write down the vapour pressure of compound C. (1) 3.2.2 Fully explain your answer to QUESTION 3.2.1. (3) 3.3 Compounds D and E are compared. 3.3.1 Which compound has the lower boiling point? (1) 3.3.2 Fully explain the difference in the vapour pressures between compounds D and E. (4) [11] Copyright reserved Please turn over

Physical Sciences/P2 9 DBE/November 2024 NSC Confidential QUESTION 4 (Start on a new page.) Study the flow diagram below. Reaction I is a CRACKING REACTION forming two organic compounds, W and T, as the ONLY products. Organic compound U Reaction I Organic Organic Organic Reaction V compound W + compound T compound S C4H8 Reaction II Reaction IV Reaction III CH3CH2CH2CH2Br Organic compound R Elimination 4.1 Define the term cracking reaction. (2) 4.2 Is the product in reaction II a PRIMARY, SECONDARY or TERTIARY haloalkane? Give a reason for the answer. (2) 4.3 Write down the: 4.3.1 STRUCTURAL FORMULA of compound W (3) 4.3.2 MOLECULAR formula of compound U (1) 4.4 For reaction II, write down: 4.4.1 The NAME or FORMULA of the inorganic reactant (1) 4.4.2 The type of reaction (Choose from SUBSTITUTION, ADDITION or ELIMINATION.) (1) 4.4.3 ONE reaction condition (1) Copyright reserved Please turn over

Physical Sciences/P2 10 DBE/November 2024 NSC Confidential The flow diagram on page 9 is redrawn below for easy reference. Organic compound U Reaction I Organic Organic Organic Reaction V compound W + compound T compound S C4H8 Reaction II Reaction IV Reaction III CH3CH2CH2CH2Br Organic compound R Elimination 4.5 Write down the TYPE of elimination in reaction III. (1) 4.6 Compounds R and T are positional isomers. The inorganic reagents shown below are available for reactions IV and V. Br2 H2SO4(conc.) NaOH(conc.) HBr H2 Write down: 4.6.1 The balanced equation for reaction IV, using STRUCTURAL FORMULAE and the correct inorganic reagent shown above (5) 4.6.2 The balanced equation for reaction V, using STRUCTURAL formulae and the correct reagent shown above (3) 4.6.3 The IUPAC name of compound T (2) [22] Copyright reserved Please turn over

Physical Sciences/P2 11 DBE/November 2024 NSC Confidential QUESTION 5 (Start on a new page.) 5.1 The reaction between pure aluminium, Aℓ(s), and EXCESS hydrochloric acid, HCℓ(aq), is used to investigate the factors that affect the rate of a reaction. The balanced equation for the reaction is: 2Aℓ(s) + 6HCℓ(aq) → 2AℓCℓ3(aq) + 3H2(g) 5.1.1 Define the term reaction rate. (2) EXPERIMENT I In this experiment, 1 mol∙dm-3 HCℓ solution reacts with a 0,5 g Aℓ strip from an aluminium roll at room temperature. The graph of volume H2(g) versus time for this experiment, not drawn to scale, is shown below. Volume H2 (dm3) 0 5 Time (minutes) 5.1.2 For the time interval t = 0 to t = 5 minutes, the average reaction rate for the formation of H2(g) is 0,033 dm3·min-1. Calculate the mass of Aℓ present in the container at t = 5 minutes. Take the molar gas volume as 24,5 dm3·mol-1. (6) Assume that the concentration of the HCℓ(aq) stays constant for the duration of the reaction. 5.1.3 Use the collision theory to explain the change in the reaction rate from t = 0 to t = 5 minutes. (4) EXPERIMENT II Experiment I is repeated using a 2 mol∙dm-3 HCℓ solution. 5.1.4 Redraw the above graph (NO numerical values need to be shown) in your ANSWER BOOK and label the curve A. On the same set of axes, draw the curve that will be obtained for Experiment II. Label this as curve B. (2) Copyright reserved Please turn over

Physical Sciences/P2 12 DBE/November 2024 NSC Confidential EXPERIMENT III Experiment I is repeated using 0,5 g pure powdered Aℓ. 5.1.5 How will the volume of H2(g) produced in Experiment III compare to that in Experiment I? Choose from GREATER THAN, LESS THAN or EQUAL TO. (1) 5.2 Curve X is the Maxwell Boltzmann distribution curve for a reaction under a set of reaction conditions. A change was made to one of the reaction conditions to obtain curve Y. Curve X Number of particles Curve Y Kinetic energy 5.2.1 What change was made to obtain curve Y? (1) 5.2.2 Give a reason for the answer to QUESTION 5.2.1. (1) [17] Copyright reserved Please turn over

Physical Sciences/P2 13 DBE/November 2024 NSC Confidential QUESTION 6 (Start on a new page.) 6.1 The reaction of carbon monoxide gas, CO(g), with oxygen gas, O2(g), is investigated. The reaction reaches equilibrium in a closed container at constant temperature T °C, according to the balanced equation: 2CO(g) + O2(g) ⇌ 2CO2(g) ΔH < 0 Changes to the conditions of equilibrium are made at different times. The graph shows the results obtained. X, Y and Z represent the gases in the above reaction. Concentration (mol∙dm-3) X Y Z 0 t1 t2 t3 Time (minutes) 6.1.1 Define the term chemical equilibrium. (2) Use the graph to answer the questions below. 6.1.2 At t1, oxygen, O2(g), was added to the container. Write down the letter that represents O2(g). Choose from X, Y or Z. (1) 6.1.3 At t2, the pressure is adjusted by changing the volume of the container. Was the pressure INCREASED or DECREASED? (1) 6.1.4 Give a reason for the answer to QUESTION 6.1.3. (1) 6.1.5 Write down the NAME or FORMULA of the gas that is represented by the letter Z. (1) 6.1.6 Give a reason for the answer to QUESTION 6.1.5. (1) 6.1.7 What change in temperature is made at t3? Choose between INCREASED or DECREASED. (1) 6.1.8 Use Le Chatelier's principle to explain the answer to QUESTION 6.1.7. (3) Copyright reserved Please turn over

Physical Sciences/P2 14 DBE/November 2024 NSC Confidential 6.2 Carbon monoxide gas, CO(g), reacts with water vapour, H2O(g), at T °C. The reaction reaches chemical equilibrium according to the balanced equation: CO(g) + H2O(g) ⇌ CO2(g) + H2(g) Initially, 0,6 moles of CO(g), 0,6 moles of H2O(g), 0,1 moles of carbon dioxide gas, CO2(g), and 0,1 moles of hydrogen gas, H2(g), were mixed and sealed in a 2 dm3 flask. If the equilibrium constant, Kc, for this reaction at T °C is 4, calculate the mass of CO(g) present in the flask at equilibrium. (9) [20] Copyright reserved Please turn over

Physical Sciences/P2 15 DBE/November 2024 NSC Confidential QUESTION 7 (Start on a new page.) Hydrated potassium carbonate, K2CO3·xH2O, is a WEAK BASE. A solution is prepared by dissolving some of this solid in water. 7.1 Define the term weak base. (2) 2- 7.2 Write down the formula of the conjugate acid of the carbonate ion, CO3 (aq). (1) A hydrochloric acid solution, HCℓ(aq), of concentration 0,1 mol·dm -3 is titrated with the prepared potassium carbonate solution, K2CO3(aq), of unknown concentration. The balanced equation for the reaction is: K2CO3(aq) + 2HCℓ(aq) → 2KCℓ(aq) + CO2(g) + H2O(ℓ) The results of the titration are given below. K2CO3(aq) IN BURETTE VOLUME OF FINAL VOLUME OF HCℓ(aq) INITIAL BURETTE K2CO3(aq) BURETTE USED (cm3) READING USED (cm3) READING (cm3) (cm3) Run 1 25 6,5 p 20,05 Run 2 25 q 48,3 20,15 7.3 Determine the value of: 7.3.1 p (1) 7.3.2 q (1) 7.4 METHYL ORANGE is used as the indicator. Explain why methyl orange is the most suitable indicator for this titration by referring to the pH at the equivalence point. (2) 7.5 Calculate the concentration of the K2CO3 solution. (5) The above K2CO3 solution used in the titration, was prepared by completely dissolving 6,525 g of the hydrated potassium carbonate, K2CO3·xH2O, in 600 cm3 water. 7.6 Calculate the value of x in the formula K2CO3·xH2O. (5) [17] Copyright reserved Please turn over

Physical Sciences/P2 16 DBE/November 2024 NSC Confidential QUESTION 8 (Start on a new page.) 8.1 Dilute hydrochloric acid, HCℓ(aq), reacts with magnesium, Mg(s), at 25 °C according to the following balanced equation: Mg(s) + 2HCℓ(aq) → MgCℓ2(aq) + H2(g) 8.1.1 Use oxidation numbers for EACH of the reactants and explain why this reaction is a redox reaction. (2) 8.1.2 Write down the FORMULA of the oxidising agent in this reaction. (1) It is observed that dilute hydrochloric acid does not react with copper, Cu(s), at 25 °C. 8.1.3 Explain this observation by referring to the relative strengths of the reducing agents. (2) 8.1.4 Will dilute nitric acid, HNO3(aq), react with copper, Cu(s), at 25 °C? Choose from YES or NO. Explain the answer in terms of the relative strengths of the oxidising agents. (3) 8.2 A galvanic cell is represented by the following cell notation: Pb(s) | Pb2+(aq) || Fe3+(aq), Fe2+(aq) | Pt(s) 8.2.1 Write down the balanced net ionic equation for this cell. (3) A stronger reducing agent is now used with the same oxidising agent under the same conditions. 8.2.2 How will this affect the initial emf of the cell? Choose from INCREASES, DECREASES or NO EFFECT. (1) [12] Copyright reserved Please turn over

Physical Sciences/P2 17 DBE/November 2024 NSC Confidential QUESTION 9 (Start on a new page.) 9.1 A strip of silver is added to a 1 mol·dm-3 solution of Pb(NO3)2 at 25 °C. Pb(NO3)2(aq) Silver strip Consider the reaction below. 2Ag(s) + Pb2+(aq) → 2Ag+(s) + Pb(s) By means of a calculation, determine whether this reaction is SPONTANEOUS or NON-SPONTANEOUS. (5) 9.2 The simplified diagram below represents an electrolytic cell. The electrodes are made of carbon. Electrode Q Concentrated NaCℓ(aq) 9.2.1 Define an electrolyte. (2) 9.2.2 Write down the PREDOMINANT oxidation half-reaction that takes place in this cell. (2) 9.2.3 Write down the NAMES or FORMULAE of the products formed at electrode Q. (2) 9.2.4 Explain the answer to QUESTION 9.2.3 by referring to the relative strengths of the oxidising agents involved. (2) [13] TOTAL: 150 Copyright reserved

Physical Sciences/P2 1 DBE/November 2024 NSC Confidential DATA FOR PHYSICAL SCIENCES GRADE 12 PAPER 2 (CHEMISTRY) GEGEWENS VIR FISIESE WETENSKAPPE GRAAD 12 VRAESTEL 2 (CHEMIE) TABLE 1: PHYSICAL CONSTANTS/TABEL 1: FISIESE KONSTANTES NAME/NAAM SYMBOL/SIMBOOL VALUE/WAARDE Standard pressure Standaarddruk p 1,013 x 105 Pa Molar gas volume at STP Vm 22,4 dm3∙mol-1 Molêre gasvolume by STD Standard temperature Standaardtemperatuur T 273 K Charge on electron e -1,6 x 10-19 C Lading op elektron Avogadro's constant NA 6,02 x 1023 mol-1 Avogadro-konstante TABLE 2: FORMULAE/TABEL 2: FORMULES m N n= n= M NA n m V c= or/of c= n= V MV Vm ca Va a n = pH = -log[H3O+] c V b b n b Kw = [H3O+][OH-] = 1 x 10-14 at/by 298 K Eθcell = Eθcathode - Eθanode /Eθsel = Eθkatode - Eθanode or/of Eθcell = Eθreduction - Eθoxidation /Eθsel = Eθreduksie - Eθoksidasie or/of Eθcell = Eθoxidising agent - Eθreducing agent /Eθsel = Eθoksideermiddel - Eθreduseermiddel Q Q where n is the number of electrons/ I= n= waar n die aantal elektrone is ∆t qe Copyright reserved Please turn over

Physical Sciences/P2 2 DBE/November 2024 NSC Confidential 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) (III) (IV) (V) (VI) (VII) (VIII) Atomic number 1 KEY/SLEUTEL Atoomgetal 2 2,1 H He 1 29 4 3 4 Electronegativity Symbol 5 6 7 8 9 10 1,0 1,5 1,9 Cu 2,0 2,5 3,0 3,5 4,0 Li Be Elektronegatiwiteit 63,5 Simbool B C N O F Ne 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 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 Copyright reserved Please turn over

Physical Sciences/P2 3 DBE/November 2024 NSC Confidential 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 Increasing strength of reducing agents /Toenemende sterkte van reduseermiddels MnO2 + 4H+ + 2e ⇌ Mn2+ + 2H2O + 1,23 Increasing strength of oxidising agents /Toenemende sterkte van oksideermiddels  Pt 2+ + 2e ⇌ Pt + 1,20  Br2(ℓ) + 2e ⇌ 2Br + 1,07 NO + 4H+ + 3e  3 ⇌ NO(g) + 2H2O + 0,96 Hg2+ + 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 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  Cd 2+ + 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 Copyright reserved Please turn over

Physical Sciences/P2 4 DBE/November 2024 NSC Confidential TABLE 4B: STANDARD REDUCTION POTENTIALS TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies EΘ (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 Increasing strength of reducing agents /Toenemende sterkte van reduseermiddels Aℓ3+ + 3e ⇌ Aℓ  1,66 Increasing strength of oxidising agents /Toenemende sterkte van oksideermiddels 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 ⇌ H2O2 + 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 Copyright reserved