Physical Sciences Grade 12 P2 NSC November 2025 QP (Eng)

Confidential NATIONAL SENIOR CERTIFICATE GRADE 12 PHYSICAL SCIENCES: CHEMISTRY (P2) NOVEMBER 2025 MARKS: 150 TIME: 3 hours This question paper consists of 16 pages and 4 data sheets. Copyright reserved Please turn over

Physical Sciences/P2 2 DBE/November 2025 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 2025 NSC Confidential QUESTION 1: MULTIPLE-CHOICE QUESTIONS 2025 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. 1.1 Which ONE of the following is the name of the functional group of propan-1-ol? A Carboxyl B Carbonyl C Hydroxyl D Formyl (2) 1.2 The organic compound C2H4 is converted to an alkane as shown by the reaction below. C2H4 → Alkane Which ONE of the following is a suitable catalyst for this reaction? A Lead B Platinum C Hydrogen D Iron (2) 1.3 Which of the following statements ALWAYS apply to compounds that are structural isomers of one another? (i) They belong to the same homologous series. (ii) They have the same structural formula. (iii) They have the same molecular formula. A (iii) only B (i) and (iii) only C (i) and (ii) only D (i), (ii) and (iii) (2) Copyright reserved Please turn over

Physical Sciences/P2 4 DBE/November 2025 NSC Confidential 1.4 Magnesium ribbon of mass 2 g reacts with excess hydrochloric acid of concentration 0,1 mol·dm-3 at 20 °C: Mg(s) + 2HCℓ(aq) → MgCℓ2(aq) + H2(g) Which ONE of the following changes will NOT increase the initial rate of the reaction? A Using 2 g of powdered magnesium B Increasing the temperature of HCℓ to 30 °C C Using a longer piece of the magnesium ribbon D Doubling the volume of the hydrochloric acid used (2) 1.5 The following reaction reaches equilibrium in a closed container: H2(g) + S(s) ⇌ H2S(g) ΔH < 0 The reaction rate versus time graph for the reaction is given below. Reaction rate t1 Time What change was made to the system at time t1? A The pressure was increased at a constant temperature. B The volume of the container was increased. C The temperature was increased. D More hydrogen was added to the system. (2) Copyright reserved Please turn over

Physical Sciences/P2 5 DBE/November 2025 NSC Confidential 1.6 A hypothetical endothermic reaction is given below. A(g) + B(g) ⇌ AB(g) The activation energy for the reverse reaction is 50 kJ∙mol-1. Which ONE of the following is possible for the reaction above? A The heat of the reaction is +70 kJ∙mol-1. B The activation energy for the forward reaction is 50 kJ∙mol-1. C The energy of the activated complex is 40 kJ∙mol-1. D The activation energy for the forward reaction is 40 kJ∙mol-1. (2) 1.7 The products for the reaction between a metal oxide and an acid are … A a salt and water. B a salt and hydrogen gas. C a salt and carbon dioxide. D a salt, water and carbon dioxide. (2) 1.8 The concentration of each of the four solutions below is 0,1 mol·dm-3. HNO3(aq), NH3(aq), NaOH(aq) and H2CO3(aq) Which ONE of the following CORRECTLY places the solutions in order of INCREASING pH? A H2CO3 ; HNO3 ; NH3 ; NaOH B HNO3 ; H2CO3 ; NH3 ; NaOH C NaOH ; NH3 ; H2CO3 ; HNO3 D HNO3 ; H2CO3 ; NaOH; NH3 (2) Copyright reserved Please turn over

Physical Sciences/P2 6 DBE/November 2025 NSC Confidential 1.9 A galvanic cell consists of the following half-cells: Fe3+(aq)|Fe2+(aq) Ni2+(aq)|Ni(s) Which ONE of the following statements is CORRECT for this cell? A Ni2+ is reduced and Fe2+ is oxidised. B Ni2+ is oxidised and Fe3+ is reduced. C Pt is the electrode at the cathode. D Ni is the electrode at the cathode. (2) 1.10 The set-up for electroplating an iron medal with silver is shown in the simplified diagram below. Power source Silver rod Iron medal Electrolyte Which ONE of the following combinations for the ANODE and REACTION AT THE CATHODE is CORRECT? ANODE REACTION AT THE CATHODE A Iron medal Ag+(aq) + e- → Ag(s) B Silver rod Fe2+(aq) + 2e- → Fe(s) C Iron medal Ag(s) → Ag+(aq) + e- D Silver rod Ag+(aq) + e- → Ag(s) (2) [20] Copyright reserved Please turn over

Physical Sciences/P2 7 DBE/November 2025 NSC Confidential QUESTION 2 (Start on a new page.) The letters A to G in the table below represent organic compounds. H H H O H H H Cℓ C C H H C C C C H H C H H A H H B H C H H H H H H C C C C C C H H H Cℓ H H H H C CH3CH(CH3)CH2CHO D C4H10O E C3H8 F Pentane H H C H H H H H C C C C C H G H H H H C H H C H H C H H 2.1 Write down the LETTER(S) that represent(s) EACH of the following: 2.1.1 An alcohol (1) 2.1.2 TWO compounds that are functional isomers of one another (1) 2.1.3 TWO compounds that belong to the same homologous series (1) 2.2 Write down the: 2.2.1 IUPAC name of compound A (3) 2.2.2 IUPAC name of compound B (3) 2.2.3 IUPAC name of compound G (3) 2.2.4 STRUCTURAL FORMULAE of two STRAIGHT CHAIN positional isomers of compound D (4) Copyright reserved Please turn over

Physical Sciences/P2 8 DBE/November 2025 NSC Confidential 2.3 Compound E, C3H8(g), reacts with oxygen, O2(g), according to the balanced equation: C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(g) Initially 8 cm3 of compound E and 50 cm3 of oxygen were injected into a container of adjustable volume and allowed to react. Reaction mixture 2.3.1 Write down the name for this type of reaction. (1) 2.3.2 Calculate the TOTAL volume of the GASES present in the container at the end of the reaction. (5) [22] Copyright reserved Please turn over

Physical Sciences/P2 9 DBE/November 2025 NSC Confidential QUESTION 3 (Start on a new page.) Two bottles contain compounds A and B with the same molecular formula, C4H8O2. These compounds are straight chain organic molecules that belong to two different homologous series. A B C4H8O2 C4H8O2 The boiling points are used to distinguish between the two compounds. 3.1 Define the term homologous series. (1) 3.2 Identify the TWO homologous series to which these compounds belong. (2) The following are the vapour pressures of these compounds at a given temperature: Compound A 0,071 kPa Compound B 9,7 kPa 3.3 Write down the: 3.3.1 STRUCTURAL FORMULA of compound A (2) 3.3.2 IUPAC name for a possible compound B (2) 3.4 Write down the strongest type of Van der Waal's forces between the molecules in: 3.4.1 Compound A (1) 3.4.2 Compound B (1) 3.5 Which compound, A or B, has a higher boiling point? Give a reason for the answer by referring to the strength of the intermolecular forces. (2) 3.6 The boiling point of compound A is measured again on another day when the atmospheric pressure is much lower. How will the boiling point of this compound now be affected? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) [12] Copyright reserved Please turn over

Physical Sciences/P2 10 DBE/November 2025 NSC Confidential QUESTION 4 (Start on a new page.) 4.1 Study the three organic reactions I, II and III below. Compounds T and W are organic compounds. R and S are inorganic substances. Consider only the major products. I HBr(g) + T W II W + NaOH(aq) CH3CH(OH)CH2CH3 + R S III CH3CH(OH)CH2CH3 T + H2O(ℓ) Write down the: 4.1.1 IUPAC name of compound W (2) 4.1.2 NAME or FORMULA of R (1) 4.1.3 TWO names for the type of reaction in reaction I (2) 4.1.4 NAME or FORMULA of S (1) 4.1.5 STRUCTURAL formula of compound T (2) Compound W can be converted to compound T in one step. 4.1.6 State, besides heat, ONE other reaction condition for this conversion. (1) 4.2 A compound with the formula C10H22 undergoes a cracking reaction according to the equation: C10H22(ℓ) → 2X(g) + C4H10(g) The mixture of the two products is bubbled in bromine water, Br2(aq), in a darkened room. 4.2.1 Define the term cracking. (2) 4.2.2 State ONE change, besides a change in temperature, that will be observed when the mixture is bubbled in Br2(aq). (1) 4.2.3 Write down the STRUCTURAL FORMULA of X. (2) 4.2.4 Which compound, X or C4H10, reacts faster with Br2(aq)? Explain the answer. (3) [17] Copyright reserved Please turn over

Physical Sciences/P2 11 DBE/November 2025 NSC Confidential QUESTION 5 (Start on a new page.) 5.1 Define the term reaction rate. (2) 5.2 Carbon monoxide, CO(g), reacts with oxygen, O2(g), to form carbon dioxide, CO2(g), in a sealed container according to the balanced equation: 2CO(g) + O2(g) → 2CO2(g) The graph below shows the concentration of O2(g) versus time. Graph of concentration of O2(g) versus time 0,30 Concentration of O2(g) (mol∙dm-3) 0,25 0,20 0,15 0,10 0,05 0 0 10 20 30 40 50 60 Time (s) 5.2.1 At which time, 10 s or 30 s, is the reaction rate higher? (1) 5.2.2 The reaction takes place in a 3 dm3 container. Calculate the average rate (in mol·s-1) at which CO2(g) is formed in the first 10 s. (5) 5.2.3 Which reactant is in excess, CO or O2? (1) 5.2.4 This reaction was repeated using a smaller sealed container. How will this affect the magnitude of the gradient of the graph at the beginning of the reaction? Choose from INCREASES, DECREASES or REMAINS THE SAME. Give a reason for the answer. (2) Copyright reserved Please turn over

Physical Sciences/P2 12 DBE/November 2025 NSC Confidential 5.3 The reaction between sulphur dioxide, SO2(g), and oxygen, O2(g), takes place in a sealed container according to the balanced equation below. 2SO2(g) + O2(g) ⇌ 2SO3(g) ΔH = -196 kJ·mol-1 5.3.1 Was there a net release or net absorption of energy during the REVERSE reaction? (1) 5.3.2 Define the term activated complex. (2) 5.3.3 A catalyst, vanadium pentoxide, is added to the reaction. Explain, in terms of the collision theory, why the rate of the reaction will increase. (3) Curve X is the Maxwell Boltzmann distribution curve for the reaction above. Number of particles X Kinetic energy More SO2(g) is now added to the container at constant temperature. 5.3.4 How will this change affect the heat of the reaction? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) 5.3.5 Redraw the above graph in the ANSWER BOOK. On the same set of axes, draw the curve that will now be obtained. Label this as curve Y. (2) [20] Copyright reserved Please turn over

Physical Sciences/P2 13 DBE/November 2025 NSC Confidential QUESTION 6 (Start on a new page.) 6.1 Equilibrium is established at 25 °C in a saturated calcium hydroxide solution according to the reaction: Ca(OH)2(s) ⇌ Ca2+(aq) + 2OH─(aq) 6.1.1 State Le Chatelier's principle. (2) 6.1.2 A few drops of concentrated hydrochloric acid, HCℓ(conc.), are added to the equilibrium mixture. What effect does this addition have on the mass of Ca(OH)2(s)? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) 6.1.3 Explain the answer to QUESTION 6.1.2 by using Le Chatelier's principle. (2) 6.2 Initially 70 g of NH4HS(s) is placed in a 3 dm3 container at 250 °C. The container is sealed and the reaction is allowed to reach equilibrium according to the balanced equation: NH4HS(s) ⇌ NH3(g) + H2S(g) The Kc values for the decomposition of NH4HS(s) at different temperatures are given in the table below. TEMPERATURE (°C) Kc 200 7,5 x 10-2 250 18 x 10-2 300 40 x 10-2 6.2.1 Is the decomposition of NH4HS(s) an EXOTHERMIC or ENDOTHERMIC reaction? (1) 6.2.2 Explain the answer to QUESTION 6.2.1 by using Le Chatelier's principle. (3) 6.2.3 Calculate the mass of NH4HS(s) that will be present at equilibrium at 250 °C. (8) [17] Copyright reserved Please turn over

Physical Sciences/P2 14 DBE/November 2025 NSC Confidential QUESTION 7 (Start on a new page.) 7.1 Phosphoric acid, H3PO4(aq), is an example of an acid that can ionise in three steps, as shown below. ─ H3PO4(aq) + H2O(ℓ) ⇌ H3O⁺(aq) + H2PO4 (aq) Ka = 6,9 x 10-3 ─ 2─ H2PO4 (aq) + H2O(ℓ) ⇌ H3O⁺(aq) + HPO4 (aq) Ka = 6,2 x 10-8 2─ 3─ HPO4 (aq) + H2O(ℓ) ⇌ H3O⁺(aq) + PO4 (aq) Ka = 4,8 x 10-13 ─ 2─ 7.1.1 Which one is the stronger acid, H2PO4 or HPO4 ? Give a reason for the answer by referring to the data above. (2) ─ 7.1.2 Write down the FORMULA for the conjugate base of H2PO4 (aq). (1) 7.1.3 Identify a substance behaving as an ampholyte in the reactions above. (1) Sodium hydrogen phosphate, Na2HPO4(s), is dissolved in water. 7.1.4 Will the resulting solution be ACIDIC or BASIC? (1) 7.1.5 Write a balanced equation to explain the answer to QUESTION 7.1.4. (3) 7.2 Barium hydroxide, Ba(OH)2, dissolves in water according to the balanced equation: Ba(OH)2(s) → Ba2+(aq) + 2OH─(aq) A 100 cm3 solution is prepared by dissolving an unknown amount of Ba(OH)2 at 25 °C. 25 cm3 of this Ba(OH)2 solution is reacted with 15 cm3 of a 0,2 mol·dm-3 HCℓ solution in a flask, according to the balanced equation: Ba(OH)2(aq) + 2HCℓ(aq) → BaCℓ2(aq) + 2H2O(ℓ) The final pH of the solution is 12,62 at 25 °C. Calculate the: 7.2.1 Final concentration of the hydroxide ions in the flask (4) 7.2.2 Number of moles of Ba(OH)2 used to prepare the 100 cm3 solution (8) [20] Copyright reserved Please turn over

Physical Sciences/P2 15 DBE/November 2025 NSC Confidential QUESTION 8 (Start on a new page.) The diagram below represents a cell that operates initially under standard conditions. V Aℓ Zn Aℓ3+(aq) Zn2+(aq) 8.1 Define the term electrolyte. (2) 8.2 Which ion concentration, Aℓ3+(aq) or Zn2+(aq), will increase? Give a reason for the answer. (2) 8.3 Write down the cell notation for this cell. (3) The electrolyte in the aluminium half-cell is prepared by dissolving some aluminium sulphate, Aℓ2(SO4)3(s), in water. 8.4 Calculate the mass of Aℓ2(SO4)3(s) needed to prepare 250 cm3 of this solution so that the cell operates initially under STANDARD CONDITIONS. (4) [11] Copyright reserved Please turn over

Physical Sciences/P2 16 DBE/November 2025 NSC Confidential QUESTION 9 (Start on a new page.) The diagram below represents a cell used for the refining of copper. • • Electrode Q Electrode R Electrolyte The unrefined copper contains zinc as the only impurity. 9.1 Is this an ELECTROLYTIC or a GALVANIC cell? (1) 9.2 When the switch is closed, it is found after T hours that the amount of Cu2+(aq) ions in the electrolyte changed by 0,05 moles and 0,15 moles of Cu(s) were deposited on electrode Q. 9.2.1 How will the concentration of the zinc ions in the electrolyte be affected during the refining of the copper? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) 9.2.2 Will the amount of Cu2+(aq) ions INCREASE or DECREASE? Explain the answer in terms of the relative strengths of the oxidising agents present. (3) 9.2.3 Calculate the change in mass of electrode R after T hours. (6) [11] TOTAL: 150 Copyright reserved

Physical Sciences/P2 1 DBE/November 2025 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 1 1,013 x 105 Pa Standaarddruk Molar gas volume at STP Vm 22,4 dm3∙mol-1 Molêre gasvolume by STD Standard temperature Tθ 273 K Standaardtemperatuur 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 θ θ θ θ θ θ Ecell = Ereduction - Eoxidation /Esel = Ereduksie - Eoksidasie or/of θ θ θ θ θ θ Ecell = Eoxidising agent - Ereducing agent /Esel = Eoksideermiddel - Ereduseermiddel Copyright reserved Please turn over

Physical Sciences/P2 2 DBE/November 2025 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 1,9 Cu 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 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 2025 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 Cr2O2− 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 Pt2+ + 2e− ⇌ Pt + 1,20 Increasing strength of oxidising agents /Toenemende sterkte van oksideermiddels Br2(ℓ) + 2e− ⇌ 2Br − + 1,07 NO−3 + 4H+ + 3e− ⇌ NO(g) + 2H2O + 0,96 Hg2+ + 2e− ⇌ Hg(ℓ) + 0,85 Ag+ + e− ⇌ Ag + 0,80 N − O3 + 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 SO2− 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 Copyright reserved Please turn over

Physical Sciences/P2 4 DBE/November 2025 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 S 2- O4 + 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 N − O3 + 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 Cr2O2- 7 + 14H + 6e + − ⇌ 2Cr3+ + 7H2O + 1,33 Cℓ2(g) + 2e− ⇌ 2Cℓ − + 1,36 Mn − O4 + 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