Physical Sciences Grade 12 P2 NSC June 2022 QP (Eng)

Downloaded from hlayiso.com SENIOR CERTIFICATE EXAMINATIONS/ NATIONAL SENIOR CERTIFICATE EXAMINATIONS PHYSICAL SCIENCES: CHEMISTRY (P2) 2022 MARKS: 150 TIME: 3 hours This question paper consists of 16 pages and 4 data sheets. Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 2 DBE/2022 SC/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 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. You may use appropriate mathematical instruments. 8. Show ALL formulae and substitutions in ALL calculations. 9. Round off your FINAL numerical answers to a minimum of TWO decimal places. 10. Give brief motivations, discussions, etc. where required. 11. You are advised to use the attached DATA SHEETS. 12. Write neatly and legibly. Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 3 DBE/2022 SC/NSC 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. 1.1 Which ONE of the following compounds has the LOWEST melting point? A Hexane B Ethane C Butane D Octane (2) 1.2 When CH2 = CH2 is converted to CH3CH3, the type of reaction is … A hydration. B hydrolysis. C halogenation. D hydrogenation. (2) 1.3 Which ONE of the following compounds in solution will change the colour of bromothymol blue? A CH3CH2CHO B CH3CH2COOH C CH3CH2COCH3 D CH3CH2COOCH3 (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 4 DBE/2022 SC/NSC 1.4 Two DIFFERENT samples of IMPURE CaCO3 of EQUAL masses react with 0,1 mol∙dm-3 H2SO4. Assume that the impurities do not react. The graph below shows the volume of CO2(g) produced for each reaction. Volume of CO2 produced (cm3) reaction 2 reaction 1 Time (s) When compared to reaction 2, which ONE of the following statements BEST explains the curve obtained for reaction 1? A The temperature is higher in reaction 1. B The surface area is greater in reaction 2. C The amount of impurities is greater in reaction 2. D The amount of impurities is greater in reaction 1. (2) 1.5 The equation below represents a hypothetical reaction. A(g) + B(g) ⇌ C(g) ΔH = - 50 kJ·mol-1 The activation energy for the REVERSE reaction is 110 kJ·mol-1. Which ONE of the following is the activation energy (in kJ·mol-1) for the FORWARD reaction? A 50 B 60 C 110 D 160 (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 5 DBE/2022 SC/NSC 1.6 A reaction reaches equilibrium at 25 °C in a flask according to the following balanced equation: Co(H2O) 26  (aq) + 4Cℓ─(aq) ⇌ CoCℓ 24  (aq) + 6H2O(ℓ) ∆H > 0 pink blue Which ONE of the following will change the colour of the mixture from pink to blue? A Adding water B Cooling the flask C Adding NaOH(aq) D Adding NH4Cℓ(aq) (2) 1.7 Dilute nitric acid is added to distilled water at 25 °C. How will this affect the hydronium ion concentration [H3O+] and the ionisation constant (Kw) of water at 25 °C? [H3O+] Kw A Increases Increases B Increases Decreases C Increases Remains the same D Remains the same Remains the same (2) 1.8 Consider the ionisation reactions I and II. I H2PO 4 + H2O(ℓ) ⇌ H3O+(aq) + X II X + H2O(ℓ) ⇌ H3O+(aq) + Y Which ONE of the following combinations represents the formulae of X and Y respectively? X Y 2 A HPO 4 PO 34 B HPO24 H3PO4 C H3PO4 PO 34 D HPO24 H2PO 4 (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 6 DBE/2022 SC/NSC 1.9 An electrochemical cell was set up using a Hg(ℓ)|Hg2+(aq) half-cell and another half-cell under standard conditions. Which ONE of the following half-cells, when connected to the Hg(ℓ)|Hg2+(aq) half-cell, will result in the HIGHEST cell potential? A Aℓ(s)|Aℓ3+(aq) B Zn(s)|Zn2+(aq) C Co(s)|Co2+(aq) D Pt(s)|H2(g)|H+(aq) (2) 1.10 The following reaction takes place in an electrochemical cell: CuCℓ2(aq) → Cu(s) + Cℓ2(g) Which ONE of the following is CORRECT for this cell? A It is a galvanic cell. B A power source is needed. C The reaction is spontaneous. D Copper acts as the oxidising agent. (2) [20] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 7 DBE/2022 SC/NSC QUESTION 2 (Start on a new page.) The letters A to H in the table below represent eight organic compounds. Br CH3 H H A CH3 CCH2 CH CH CH3 B H C C C C H CH3 CH3 H H H H C Pent-2-ene D CH3CH2CH2CHO E Butan-2-one F 4,4-dimethylpent-2-yne G Butane H CH3CH2CH2COOH 2.1 Write down the LETTER that represents a compound that: 2.1.1 Is a ketone (1) 2.1.2 Has the general formula CnH2n-2 (1) 2.1.3 Is an isomer of 2-methylbut-2-ene (1) 2.1.4 Has the same molecular formula as ethyl ethanoate (1) 2.2 Write down the: 2.2.1 IUPAC name of compound A (3) 2.2.2 STRUCTURAL FORMULA of compound F (3) 2.3 For compound D, write down the: 2.3.1 Homologous series to which it belongs (1) 2.3.2 NAME of its functional group (1) 2.3.3 STRUCTURAL FORMULA of its functional isomer (2) 2.4 For compound G, write down: 2.4.1 The IUPAC name of a chain isomer (2) 2.4.2 A balanced equation, using molecular formulae, for its complete combustion (3) [19] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 8 DBE/2022 SC/NSC QUESTION 3 (Start on a new page.) Learners investigate factors that influence the boiling points of organic compounds. The boiling points of some organic compounds obtained are shown in the table below. MOLECULAR MASS BOILING POINT COMPOUND (g∙mol-1) (°C) A Propane 44 - 42 B Butane 58 - 0,5 C Pentane 72 36 D Methylbutane 72 28 E Ethanol 46 78 F Ethanal 44 20 3.1 Define the term boiling point. (2) 3.2 The boiling points of compounds A, B and C are compared. 3.2.1 How do the boiling points vary from compound A to compound C? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) 3.2.2 Explain the answer to QUESTION 3.2.1. (3) 3.3 The boiling points of compounds B, C and D are compared. Is this a fair comparison? Choose from YES or NO. Give a reason for the answer. (2) 3.4 The boiling points of compounds E and F are compared. 3.4.1 State the independent variable for this comparison. (1) 3.4.2 Write down the name of the strongest Van der Waals force present in compound F. (1) 3.5 Which compound, D or E, has a higher vapour pressure? Give a reason for the answer. (2) [12] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 9 DBE/2022 SC/NSC QUESTION 4 (Start on a new page.) 4.1 Study the following incomplete equations for organic reactions I and II. Compounds P and Q are ORGANIC compounds and T is an INORGANIC compound. CH3 I CH3 CH CH CH3 + NaOH (conc.) P + NaBr + T (major product) Br II CH3COOH + compound Q → butyl ethanoate + H2O For reaction I, write down the: 4.1.1 Type of reaction that takes place (1) 4.1.2 IUPAC name of compound P (2) 4.1.3 NAME or FORMULA of compound T (1) For reaction II, write down: 4.1.4 TWO reaction conditions needed (2) 4.1.5 The STRUCTURAL FORMULA of compound Q (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 10 DBE/2022 SC/NSC 4.2 The cracking of a long chain hydrocarbon, C10H22, takes place in test tube A, as shown below. cotton wool soaked in C10H22 A Aℓ2O3(s) Br2(aq) B Two STRAIGHT CHAIN organic compounds, X and Z, are produced in test tube A according to the following balanced equation: C10H22(ℓ) → 2X(g) + Z(g) 4.2.1 State the function of the Aℓ2O3(s) in test tube A. (1) The organic compounds, X and Z, are now passed through bromine water, Br2(aq), at room temperature in test tube B. Only compound X reacts with the bromine water. 4.2.2 Apart from gas bubbles being formed, state another observable change in test tube B. (1) 4.2.3 Write down the TYPE of reaction that takes place in test tube B. (1) 4.2.4 Write down the molecular formula of compound Z. (3) 4.2.5 Write down the STRUCTURAL FORMULA of compound X. (3) [17] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 11 DBE/2022 SC/NSC QUESTION 5 (Start on a new page.) Learners use the reaction of MgCO3(s) with EXCESS dilute HCℓ(aq) to investigate the relationship between temperature and the rate of a chemical reaction. The balanced equation for the reaction is: MgCO3(s) + 2HCℓ(aq) → MgCℓ2(aq) + CO2(g) + H2O(ℓ) The results obtained are represented in the graph below. Graph of average rate of production of CO2 (in g·min-1) versus temperature 0,6 Average rate of production of CO2 0,5 0,4 (g·min-1) 0,3 0,2 0,1 0 0 10 20 30 40 50 Temperature (°C) 5.1 Define the term rate of reaction. (2) 5.2 State TWO conditions that must be kept constant during this investigation. (2) 5.3 Use the collision theory to explain the relationship shown in the graph. (4) 5.4 The learners obtained the graph above using 5 g MgCO3(s) with EXCESS HCℓ at 40 °C. Calculate the: 5.4.1 Time taken for the reaction to run to completion (6) 5.4.2 Molar gas volume at 40 °C if 1,5 dm3 CO2 is collected in a syringe (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 12 DBE/2022 SC/NSC 5.5 The graph below represents the Maxwell-Boltzmann distribution curve for CO2(g) at 40 °C. Number of CO2 molecules A Kinetic energy Redraw the graph above in the ANSWER BOOK. Clearly label the curve as A. On the same set of axes, sketch the curve that will be obtained for the CO2(g) at 20 °C. Label this curve as B. (2) [18] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 13 DBE/2022 SC/NSC QUESTION 6 (Start on a new page.) 6.1 Initially, 4 moles H2(g) and 4 moles I2(g) are allowed to react in a sealed 2 dm3 flask according to the following balanced equation: H2(g) + I2(g) ⇌ 2HI(g) ΔH < 0 The graph below shows the concentrations of H2(g) and HI(g) versus time during the reaction. Concentration (mol·dm-3) Y H2 HI 0 t1 t2 Time (s) 6.1.1 Write down the value of Y. (1) 6.1.2 State Le Chatelier's principle. (2) 6.1.3 Changes were made to the temperature of the flask at time t2. Was the flask HEATED or COOLED? (1) 6.1.4 Fully explain the answer to QUESTION 6.1.3. (3) 6.2 The equation below represents the reversible reaction that takes place when NO2(g) is converted to N2O4(g). 2NO2(g) ⇌ N2O4(g) Initially, x mol of NO2(g) is sealed in a 1 dm3 container at 350 K. When equilibrium is established at this temperature, 0,81 mol N2O4(g) is present in the container. 6.2.1 Write down the meaning of the term reversible reaction. (1) 6.2.2 Show that the equilibrium constant for this reaction is given by 0,81 . ( x  1,62) 2 (5) 0,79 moles of N2O4(g) is now added to the equilibrium mixture above. When the NEW equilibrium is established at 350 K, it is found that the amount of NO2(g) increased by 1,2 moles. 6.2.3 Calculate the value of x. (6) [19] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 14 DBE/2022 SC/NSC QUESTION 7 (Start on a new page.) 7.1 Two acids, HX and HY, of EQUAL CONCENTRATIONS are compared. The pH of HX is 2,7 and the pH of HY is 0,7. 7.1.1 Define an acid in terms of the Lowry-Brønsted theory. (2) 7.1.2 Which acid, HX or HY, is STRONGER? Give a reason for the answer. (2) 7.1.3 Acid HX ionises in water according to the following equation: HX(aq) + H2O(ℓ) ⇌ H3O+(aq) + X─(aq) The Ka value for the reaction is 1,8 x 10-5 at 25 °C. Is the concentration of the hydronium ions HIGHER THAN, LOWER THAN or EQUAL TO the concentration of HX? Give a reason for the answer. (2) 7.2 Learners add 150 cm3 of a sodium hydroxide solution, NaOH, of unknown concentration to 200 cm3 of a 0,03 mol∙dm-3 hydrochloric acid solution, HCℓ, as illustrated below. They find that the pH of the final solution is 2. Assume that the volumes are additive. NaOH(aq) 150 cm3 200 cm3 pH = 2 0,03 mol∙dm-3 HCℓ final solution The balanced equation for the reaction is: HCℓ(aq) + NaOH(aq) → NaCℓ(aq) + H2O(ℓ) Calculate the: 7.2.1 Concentration of the H3O+ ions in the final solution (3) 7.2.2 Initial concentration of the NaOH(aq) (7) [16] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 15 DBE/2022 SC/NSC QUESTION 8 (Start on a new page.) 8.1 An electrochemical cell is set up using an aluminium rod, Aℓ, and a gas X. The initial emf measured under standard conditions is 2,89 V. 8.1.1 State the standard conditions under which this cell operates. (3) 8.1.2 Use a calculation to identify gas X. (5) 8.1.3 Write down the FORMULA of the reducing agent in this cell. (1) 8.1.4 Write down the half-reaction that takes place at the cathode. (2) 8.1.5 Write down the cell notation for this cell. (3) 8.2 Which container, ZINC or COPPER, will be more suitable to store an aqueous solution of nickel ions, Ni2+? Refer to the Table of Standard Reduction Potentials to fully explain the answer in terms of the relative strengths of reducing agents. (4) [18] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 16 DBE/2022 SC/NSC QUESTION 9 (Start on a new page.) The simplified diagram below represents an electrochemical cell used for the electrolysis of a concentrated sodium chloride solution, NaCℓ(aq). X and Y are carbon electrodes. power source electrode Y electrode X concentrated NaCℓ(aq) 9.1 Define the term electrolysis. (2) 9.2 Chlorine gas, Cℓ2(g), is released at electrode X. Write down the: 9.2.1 Letter (X or Y) of the electrode where oxidation takes place (1) 9.2.2 Half-reaction that takes place at electrode Y (2) 9.2.3 Direction in which electrons flow in the external circuit Choose from X to Y OR Y to X. (1) 9.2.4 Balanced equation for the net (overall) cell reaction that takes place in the cell (3) 9.3 How will the pH of the electrolyte change during the reaction? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) 9.4 Give a reason for the answer to QUESTION 9.3. (1) [11] TOTAL: 150 Copyright reserved

Downloaded from hlayiso.com Physical Sciences/P2 1 DBE/2022 SC/NSC 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 p 1,013 x 105 Pa Standaarddruk 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 c a v a na  pH = -log[H3O+] c b v b nb Kw = [H3O+][OH-] = 1 x 10-14 at/by 298 K Eθcell  Eθcathode  Eθanode / Eθsel  Ekatode θ  Eθanode or/of Eθcell  Ereduction θ  Eθoxidation / Eθsel  Ereduksie θ  Eθoksidasie or/of Eθcell  Eθoxidising agent  Ereducing θ agent / E sel  Eoksideermiddel  Ereduseermiddel θ θ θ Q Q n= or/of n= e qe Copyright reserved Please turn over

Physical Sciences/P2 Downloaded from hlayiso.com 2 DBE/2022 SC/NSC 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

Downloaded from hlayiso.com Physical Sciences/P2 3 DBE/2022 SC/NSC TABLE 4A: STANDARD REDUCTION POTENTIALS TABEL 4A: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E θ (V) F2(g) + 2e ⇌ 2F + 2,87 3+  2+ Co +e ⇌ Co + 1,81 H2O2 + 2H +2e + ⇌ 2H2O +1,77  + 8H + 5e 2+ ⇌ + MnO 4 Mn + 4H2O + 1,51   Cℓ2(g) + 2e ⇌ 2Cℓ + 1,36 2 Cr2O 7 + 14H + 6e + 3+ ⇌ 2Cr + 7H2O + 1,33 +  O2(g) + 4H + 4e ⇌ 2H2O + 1,23 +  2+ MnO2 + 4H + 2e ⇌ Mn + 2H2O + 1,23 + 2e 2+ Pt ⇌ Pt + 1,20   Br2(ℓ) + 2e ⇌ 2Br + 1,07  +  NO 3 + 4H + 3e ⇌ NO(g) + 2H2O + 0,96 Increasing strength of oxidising agents/Toenemende sterkte van oksideermiddels Increasing strength of reducing agents/Toenemende sterkte van reduseermiddels 2+  Hg + 2e ⇌ Hg(ℓ) + 0,85 Ag + e + ⇌ Ag + 0,80  +  NO 3 + 2H + e ⇌ NO2(g) + H2O + 0,80 + e 3+ 2+ Fe ⇌ Fe + 0,77 O2(g) + 2H + 2e + ⇌ H2O2 + 0,68   I2 + 2e ⇌ 2I + 0,54 +  Cu + e ⇌ Cu + 0,52 SO2 + 4H + 4e + + 0,45 ⇌ S + 2H2O 2H2O + O2 + 4e ⇌ 4OH + 0,40 2+  Cu + 2e ⇌ Cu + 0,34 2 SO 4 + 4H + 2e ⇌ + SO2(g) + 2H2O + 0,17 2+  + Cu +e ⇌ Cu + 0,16 4+  2+ Sn + 2e ⇌ Sn + 0,15 S + 2H + 2e + ⇌ H2S(g) + 0,14 +  2H + 2e ⇌ H2(g) 0,00 + 3e  0,06 3+ Fe ⇌ Fe + 2e  0,13 2+ Pb ⇌ Pb + 2e  0,14 2+ Sn ⇌ Sn + 2e  0,27 2+ Ni ⇌ Ni   0,28 2+ Co + 2e ⇌ Co + 2e  0,40 2+ Cd ⇌ Cd  2+  0,41 3+ Cr +e ⇌ Cr + 2e  0,44 2+ Fe ⇌ Fe   0,74 3+ Cr + 3e ⇌ Cr + 2e  0,76 2+ Zn ⇌ Zn   2H2O + 2e ⇌ H2(g) + 2OH  0,83 + 2e  0,91 2+ Cr ⇌ Cr   1,18 2+ Mn + 2e ⇌ Mn + 3e  1,66 3+ Aℓ ⇌ Aℓ   2,36 2+ Mg + 2e ⇌ Mg Na + e  2,71 + ⇌ Na + 2e  2,87 2+ Ca ⇌ Ca   2,89 2+ Sr + 2e ⇌ Sr + 2e  2,90 2+ Ba ⇌ Ba + - Cs + e ⇌ Cs - 2,92 K + e  2,93 + ⇌ K Li + e  3,05 + ⇌ Li Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 4 DBE/2022 SC/NSC TABLE 4B: STANDARD REDUCTION POTENTIALS TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE Half-reactions/Halfreaksies E θ (V) Li + e  3,05 + ⇌ Li K + e  2,93 + ⇌ K   2,92 + Cs + e ⇌ Cs + 2e  2,90 2+ Ba ⇌ Ba   2,89 2+ Sr + 2e ⇌ Sr + 2e  2,87 2+ Ca ⇌ Ca Na + e  2,71 + ⇌ Na   2,36 2+ ⇌ Increasing strength of oxidising agents/Toenemende sterkte van oksideermiddels Mg + 2e Mg Increasing strength of reducing agents/Toenemende sterkte van reduseermiddels + 3e  1,66 3+ Aℓ ⇌ Aℓ   1,18 2+ Mn + 2e ⇌ Mn + 2e  0,91 2+ Cr ⇌ Cr   2H2O + 2e ⇌ H2(g) + 2OH  0,83 + 2e  0,76 2+ Zn ⇌ Zn   0,74 3+ Cr + 3e ⇌ Cr + 2e  0,44 2+ Fe ⇌ Fe  2+  0,41 3+ Cr +e ⇌ Cr + 2e  0,40 2+ Cd ⇌ Cd   0,28 2+ Co + 2e ⇌ Co + 2e  0,27 2+ Ni ⇌ Ni + 2e  0,14 2+ Sn ⇌ Sn   0,13 2+ Pb + 2e ⇌ Pb + 3e  0,06 3+ Fe ⇌ Fe +  2H + 2e ⇌ H2(g) 0,00 S + 2H + 2e + ⇌ H2S(g) + 0,14 4+  2+ Sn + 2e ⇌ Sn + 0,15 + e 2+ + Cu ⇌ 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 3+  2+ Fe +e ⇌ Fe + 0,77  +  NO 3 + 2H + e ⇌ NO2(g) + H2O + 0,80 +  Ag + e ⇌ Ag + 0,80 2+  Hg + 2e ⇌ Hg(ℓ) + 0,85  + 4H + 3e + NO 3 ⇌ NO(g) + 2H2O + 0,96   Br2(ℓ) + 2e ⇌ 2Br + 1,07 + 2 e 2+ Pt ⇌ Pt + 1,20 +  2+ MnO2 + 4H + 2e ⇌ Mn + 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  +  2+ MnO 4 + 8H + 5e ⇌ Mn + 4H2O + 1,51 +  H2O2 + 2H +2 e ⇌ 2H2O +1,77 3+  2+ Co +e ⇌ Co + 1,81 F2(g) + 2e ⇌ 2F + 2,87 Copyright reserved