Physical Sciences Grade 12 P2 NSC November Mock 2026 QP

Mock hlayiso mock exams Practice Series: Grade 12 NSC Preparation WWW.HLAYISO.COM NATIONAL SENIOR CERTIFICATE GRADE 12 PHYSICAL SCIENCES: CHEMISTRY (P2) MOCK EXAMINATION 2026 MARKS: 150 TIME: 3 hours This question paper consists of 13 pages and 4 data sheets. Copyright reserved Please turn over

Physical Sciences/P2 2 Hlayiso/Mock 2026 NSC Mock INSTRUCTIONS AND INFORMATION 1. Write your name and class (or 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 Hlayiso/Mock 2026 NSC Mock 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 is the general formula of the ALKYNES? A Cn H2n+2 B Cn H2n C Cn H2n–2 D Cn H2n+1 OH (2) 1.2 Which ONE of the following compounds is an ESTER? A CH3 COOH B CH3 COOCH2 CH3 C CH3 COCH3 D CH3 CH2 CHO (2) 1.3 Propene reacts with water in the presence of an acid catalyst. The MAJOR product of this reaction is … A propan-2-ol. B propan-1-ol. C propane. D propanal. (2) 1.4 Which ONE of the following changes will LOWER the activation energy of a reaction? A Increasing the temperature B Increasing the concentration of the reactants C Increasing the surface area of a solid reactant D Adding a catalyst (2) Copyright reserved Please turn over

Physical Sciences/P2 4 Hlayiso/Mock 2026 NSC Mock 1.5 For a certain reaction, the activation energy of the FORWARD reaction is 80 kJ·mol–1 and the heat of reaction (∆H) is –50 kJ·mol–1 . The activation energy of the REVERSE reaction (in kJ·mol–1 ) is … A 30 B 130 C 50 D 80 (2) 1.6 The reaction below reaches equilibrium in a closed container. N2 (g) + 3H2 (g) ⇌ 2NH3 (g) ∆H < 0 Which ONE of the following changes will increase BOTH the yield of NH3 (g) AND the value of the equilibrium constant, Kc ? A Decreasing the temperature B Increasing the pressure by decreasing the volume C Adding a catalyst D Increasing the temperature (2) 1.7 The equilibrium constant for a reaction at 25 ◦ C is 2,5 × 10–4 . Which ONE of the following statements about this reaction at 25 ◦ C is CORRECT? A The concentration of the products is higher than that of the reactants at equilibrium. B The reaction goes to completion. C The equilibrium position lies to the left (reactants are favoured). D The rate of the forward reaction is higher than the rate of the reverse (2) reaction at equilibrium. 1.8 Which ONE of the following salts will form a BASIC solution when it dissolves in water? A NaCℓ B NH4 Cℓ C KNO3 D Na2 CO3 (2) Copyright reserved Please turn over

Physical Sciences/P2 5 Hlayiso/Mock 2026 NSC Mock 1.9 The pH of a solution at 25 ◦ C is 4. The concentration of the hydroxide ions, [OH– ], in this solution (in mol·dm–3 ) is … A 1 × 10–10 B 1 × 10–4 C 1 × 104 D 1 × 10–14 (2) 1.10 Which ONE of the following combinations is CORRECT for the ANODE of an ELECTROLYTIC cell? POLARITY HALF-REACTION A Negative Oxidation B Positive Oxidation (2) C Positive Reduction D Negative Reduction [20] Copyright reserved Please turn over

Physical Sciences/P2 6 Hlayiso/Mock 2026 NSC Mock QUESTION 2 (Start on a new page.) The letters A to F in the table below represent six organic compounds. H H H A B C CH3 CH2 COCH2 CH3 H Cℓ H H H H C C C C C C H H H H H H C H H H H H H H O C CH3 CH2 CH2 COOH D H C C C C C H H H H H H H H H O H E C F H H H H C C C H H C C C C C H H H C H H H H H C H H H H 2.1 Write down the LETTER(S) that represent(s) EACH of the following: 2.1.1 A carboxylic acid (1) 2.1.2 A TERTIARY alcohol (1) 2.1.3 TWO compounds that are functional isomers of each other (1) 2.2 Write down the IUPAC name of: 2.2.1 Compound B (3) 2.2.2 Compound E (3) 2.2.3 Compound A (2) 2.3 Compound C reacts with alcohol X in the presence of a catalyst to form an ester with molecular formula C6 H12 O2 . 2.3.1 Write down the type of reaction that takes place. (1) 2.3.2 Write down the NAME or FORMULA of the catalyst used. (1) 2.3.3 Write down the IUPAC name of alcohol X. (1) Copyright reserved Please turn over

Physical Sciences/P2 7 Hlayiso/Mock 2026 NSC Mock 2.3.4 Write down the STRUCTURAL FORMULA of the ester. (2) 2.3.5 Write down the IUPAC name of the ester. (2) 2.4 Define the term functional isomers. (2) [20] QUESTION 3 (Start on a new page.) Learners investigate the boiling points of four organic compounds, A to D. The results are shown in the table below. COMPOUND IUPAC NAME MOLAR MASS (g·mol–1 ) BOILING POINT (◦ C) A Pentane 72 36 B Butanal 72 75 C Butan-1-ol 74 118 D Propanoic acid 74 141 3.1 Define the term boiling point. (2) 3.2 Give a reason why this is a FAIR comparison. (1) 3.3 Which compound (A, B, C or D) has the HIGHEST vapour pressure at 25 ◦ C? (1) 3.4 Explain the difference in the boiling points of compounds C and D. (3) 3.5 Fully explain why the boiling point of compound B is higher than that of compound A by referring to the TYPES of intermolecular forces. (4) 3.6 Compound A is replaced by its chain isomer, 2,2-dimethylpropane. Will the boiling point of 2,2-dimethylpropane be HIGHER THAN or LOWER THAN that of compound A? Give a reason for the answer. (2) [13] QUESTION 4 (Start on a new page.) The flow diagram below shows how but-1-ene can be used to prepare other organic compounds. P and Q represent organic compounds. Consider only MAJOR products. Reaction I But-1-ene Compound P HBr I at Reaction V i o n I ld he t mi ac Reaction III H2 O, H3 PO4 Re (aq), H aO t eN dilu Reaction IV Butan-2-ol Compound Q conc. H2 SO4 , heat 4.1 Write down the TYPE of reaction represented by: Copyright reserved Please turn over

Physical Sciences/P2 8 Hlayiso/Mock 2026 NSC Mock 4.1.1 Reaction I (1) 4.1.2 Reaction II (1) 4.1.3 Reaction IV (1) 4.2 Write down the STRUCTURAL FORMULA of compound P. (2) 4.3 For Reaction III, write down the: 4.3.1 Type of elimination reaction (1) 4.3.2 TWO reaction conditions (2) 4.3.3 IUPAC name of compound Q (2) 4.4 Use STRUCTURAL FORMULAE to write down a balanced equation for Reaction V. (3) 4.5 Compound Q undergoes complete combustion in excess oxygen. Use MOLECULAR FORMULAE to write down a balanced equation for this reaction. (3) 4.6 Butane can be obtained by the cracking of decane, as shown by the equation below. C10 H22 → C4 H10 + 2X Write down the IUPAC name of compound X. (1) [17] Copyright reserved Please turn over

Physical Sciences/P2 9 Hlayiso/Mock 2026 NSC Mock QUESTION 5 (Start on a new page.) Learners investigate factors that affect the rate of the reaction between calcium carbonate, CaCO3 (s), and EXCESS hydrochloric acid, HCℓ(aq). The balanced equation for the reaction is: CaCO3 (s) + 2HCℓ(aq) → CaCℓ2 (aq) + H2 O(ℓ) + CO2 (g) In each experiment, 2 g of CaCO3 is added to 50 cm3 of hydrochloric acid. The conditions used are shown in the table below. EXPERIMENT STATE OF DIVISION CONCENTRATION OF TEMPERATURE OF CaCO3 HCℓ (mol·dm–3 ) (◦ C) 1 Lumps 1 25 2 Powder 1 25 3 Lumps 2 25 4 Lumps 1 40 5.1 Define the term reaction rate. (2) 5.2 For the comparison of experiments 1 and 3, write down the: 5.2.1 Independent variable (1) 5.2.2 ONE controlled variable (1) 5.3 Use the collision theory to explain why the initial reaction rate in experiment 2 is higher than in experiment 1. (3) 5.4 Use the collision theory to explain why the initial reaction rate in experiment 4 is higher than in experiment 1. (3) 5.5 In experiment 1, the average rate of production of CO2 (g) during the first 60 s is 1,5 × 10–4 mol·s–1 . Calculate the mass of CaCO3 (s) that REMAINS in the flask after 60 s. (4) 5.6 The volume of CO2 (g) produced in experiments 1 and 3 is measured until the reactions stop. Sketch the graphs of volume of CO2 (g) versus time for experiments 1 and 3 on the same set of axes. Label the graphs as 1 and 3. (3) [17] Copyright reserved Please turn over

Physical Sciences/P2 10 Hlayiso/Mock 2026 NSC Mock QUESTION 6 (Start on a new page.) Methanol, CH3 OH, is produced industrially from carbon monoxide and hydrogen according to the balanced equation: CO(g) + 2H2 (g) ⇌ CH3 OH(g) ∆H < 0 Initially 0,8 mol CO(g) and 1,2 mol H2 (g) are sealed in a 2 dm3 container at temperature T. When equilibrium is reached, 0,3 mol CH3 OH(g) is present in the container. 6.1 State Le Chatelier’s principle. (2) 6.2 Calculate the equilibrium constant, Kc , for this reaction at temperature T. (8) 6.3 The temperature of the system is now INCREASED. 6.3.1 How will the value of Kc be affected? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) 6.3.2 Explain the answer to QUESTION 6.3.1. (3) 6.4 The temperature is returned to T and the pressure is increased by DECREASING the volume of the container. 6.4.1 How will the yield of CH3 OH(g) be affected? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) 6.4.2 Use Le Chatelier’s principle to explain the answer to QUESTION 6.4.1. (3) 6.5 A catalyst is now added to the system at equilibrium. How will this affect the number of moles of CH3 OH(g) at equilibrium? Choose from INCREASES, DECREASES or REMAINS THE SAME. Give a reason for the answer. (2) [20] Copyright reserved Please turn over

Physical Sciences/P2 11 Hlayiso/Mock 2026 NSC Mock QUESTION 7 (Start on a new page.) 7.1 Define a base according to the Lowry-Brønsted theory. (2) 7.2 Ammonium chloride, NH4 Cℓ(s), is dissolved in water. 7.2.1 Will the solution be ACIDIC, BASIC or NEUTRAL? (1) 7.2.2 Write down a balanced equation to explain the answer to QUESTION 7.2.1. (3) 7.3 A learner dissolves 3,2 g of sodium hydroxide, NaOH(s), in water to prepare 250 cm3 of solution X at 25 ◦ C. 7.3.1 Calculate the pH of solution X. (5) 25 cm3 of solution X is added to 30 cm3 of a 0,15 mol·dm–3 sulphuric acid solution, H2 SO4 (aq). The balanced equation for the reaction is: 2NaOH(aq) + H2 SO4 (aq) → Na2 SO4 (aq) + 2H2 O(ℓ) 7.3.2 Calculate the pH of the final solution. Assume that H2 SO4 ionises completely and that the volumes are additive. (8) [19] Copyright reserved Please turn over

Physical Sciences/P2 12 Hlayiso/Mock 2026 NSC Mock QUESTION 8 (Start on a new page.) The galvanic cell shown below operates under standard conditions. V salt bridge Ni Ag Ni2+ (aq) Ag+ (aq) 8.1 Write down the standard conditions under which this cell operates. (2) 8.2 State ONE function of the salt bridge. (1) 8.3 Which electrode, Ni or Ag, is the ANODE? (1) 8.4 Write down the balanced net (overall) cell reaction that takes place in this cell. (3) 8.5 Calculate the initial emf of this cell. (4) 8.6 The concentration of the Ag+ (aq) ions is now increased. How will the emf of the cell be affected? Choose from INCREASES, DECREASES or REMAINS THE SAME. (1) [12] QUESTION 9 (Start on a new page.) A concentrated copper(II) chloride solution, CuCℓ2 (aq), is electrolysed using two carbon electrodes, A and B, as shown in the simplified diagram below. +– A B CuCℓ2 (aq) 9.1 Define the term electrolysis. (2) 9.2 Write down the half-reaction that takes place at electrode B. (2) 9.3 Write down the NAME or FORMULA of the gas formed at electrode A. (1) Copyright reserved Please turn over

Physical Sciences/P2 13 Hlayiso/Mock 2026 NSC Mock 9.4 During the electrolysis, 0,635 g of copper is deposited. Calculate the volume of the gas formed at electrode A, measured at STP. (4) 9.5 Electrode A is now replaced with a COPPER electrode. How will the concentration of the Cu2+ (aq) ions in the solution change during electrolysis? Choose from INCREASES, DECREASES or REMAINS THE SAME. Explain the answer by referring to the relative strengths of the reducing agents. (3) [12] TOTAL: 150 Copyright reserved Please turn over

Physical Sciences/P2 1 Hlayiso/Mock 2026 NSC Mock DATA FOR PHYSICAL SCIENCES GRADE 12 PAPER 2 (CHEMISTRY) TABLE 1: PHYSICAL CONSTANTS NAME SYMBOL VALUE Standard pressure pθ 1,013× 105 Pa Molar gas volume at STP Vm 22,4 dm3 ·mol–1 Standard temperature Tθ 273 K Charge on electron e 1,6× 10–19 C Avogadro’s constant NA 6,02× 1023 mol–1 TABLE 2: FORMULAE m N n= n= M NA n m V c= or c = n= V MV Vm ca Va na = pH = – log[H3 O+ ] cb Vb nb Kw = [H3 O+ ][OH– ] = 1 × 10–14 at 298 K Eθcell = Eθcathode – Eθanode or Ecell = Ereduction – Eθoxidation θ θ or Ecell = Eoxidising agent – Eθreducing agent θ θ Copyright reserved Please turn over

Physical Sciences/P2 2 Hlayiso/Mock 2026 NSC Mock TABLE 3: THE PERIODIC TABLE OF ELEMENTS 1 2 13 14 15 16 17 18 (I) (II) 3 4 5 6 7 8 9 10 11 12 (III) (IV) (V) (VI) (VII) (VIII) 1 2 Atomic number 2,1 H He 1 KEY 4 29 3 4 5 6 7 8 9 10 1,0 1,5 Electronegativity 1,9 Cu Symbol 2,0 2,5 3,0 3,5 4,0 Li Be B C N O F Ne 7 9 63,5 11 12 14 16 19 20 11 12 13 14 15 16 17 18 0,9 Na 1,2 Mg 1,5 Aℓ 1,8 Si 2,1 P 2,5 S 3,0 Cℓ Ar Approximate relative atomic mass 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 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

Physical Sciences/P2 3 Hlayiso/Mock 2026 NSC Mock TABLE 4A: STANDARD REDUCTION POTENTIALS Half-reactions Eθ (V) F2 (g) + 2e– ⇌ 2F– + 2,87 Co3+ + e– ⇌ Co2+ + 1,81 H2 O2 + 2H+ + 2e– ⇌ 2H2 O + 1,77 MnO–4 + 8H+ + 5e– ⇌ Mn2+ + 4H2 O + 1,51 Cℓ2 (g) + 2e– ⇌ 2Cℓ– + 1,36 Cr2 O2– + – 3+ 7 + 14H + 6e ⇌ 2Cr + 7H2 O + 1,33 + – O2 (g) + 4H + 4e ⇌ 2H2 O + 1,23 MnO2 + 4H+ + 2e– ⇌ Mn2+ + 2H2 O + 1,23 Pt2+ + 2e– ⇌ Pt + 1,20 Br2 (ℓ) + 2e– ⇌ 2Br– + 1,07 NO–3 + 4H+ + 3e– ⇌ NO(g) + 2H2 O + 0,96 Hg2+ + 2e– ⇌ Hg(ℓ) + 0,85 Ag+ + e– ⇌ Ag + 0,80 NO3 + 2H+ + e– ⇌ NO2 (g) + H2 O – + 0,80 Fe3+ + e– ⇌ Fe2+ + 0,77 O2 (g) + 2H+ + 2e– ⇌ H2 O2 + 0,68 Increasing strength of oxidising agents I2 + 2e– ⇌ 2I– Increasing strength of reducing agents + 0,54 Cu+ + e– ⇌ Cu + 0,52 SO2 + 4H+ + 4e– ⇌ S + 2H2 O + 0,45 2H2 O + O2 + 4e– ⇌ 4OH– + 0,40 Cu2+ + 2e– ⇌ Cu + 0,34 SO4 + 4H+ + 2e– ⇌ SO2 (g) + 2H2 O 2– + 0,17 Cu2+ + e– ⇌ Cu+ + 0,16 Sn4+ + 2e– ⇌ Sn2+ + 0,15 S + 2H+ + 2e– ⇌ H2 S(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 2H2 O + 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 Hlayiso/Mock 2026 NSC Mock TABLE 4B: STANDARD REDUCTION POTENTIALS Half-reactions 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 Aℓ3+ + 3e– ⇌ Aℓ – 1,66 Mn2+ + 2e– ⇌ Mn – 1,18 Cr2+ + 2e– ⇌ Cr – 0,91 2H2 O + 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 Increasing strength of oxidising agents Cd2+ + 2e– ⇌ Cd Increasing strength of reducing agents – 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– ⇌ H2 S(g) + 0,14 Sn4+ + 2e– ⇌ Sn2+ + 0,15 Cu2+ + e– ⇌ Cu+ + 0,16 SO4 + 4H+ + 2e– ⇌ SO2 (g) + 2H2 O 2– + 0,17 Cu2+ + 2e– ⇌ Cu + 0,34 2H2 O + O2 + 4e– ⇌ 4OH– + 0,40 SO2 + 4H+ + 4e– ⇌ S + 2H2 O + 0,45 Cu+ + e– ⇌ Cu + 0,52 I2 + 2e– ⇌ 2I– + 0,54 O2 (g) + 2H+ + 2e– ⇌ H2 O2 + 0,68 Fe3+ + e– ⇌ Fe2+ + 0,77 NO–3 + 2H+ + e– ⇌ NO2 (g) + H2 O + 0,80 Ag+ + e– ⇌ Ag + 0,80 Hg2+ + 2e– ⇌ Hg(ℓ) + 0,85 NO–3 + 4H+ + 3e– ⇌ NO(g) + 2H2 O + 0,96 Br2 (ℓ) + 2e– ⇌ 2Br– + 1,07 Pt2+ + 2e– ⇌ Pt + 1,20 MnO2 + 4H+ + 2e– ⇌ Mn2+ + 2H2 O + 1,23 O2 (g) + 4H+ + 4e– ⇌ 2H2 O + 1,23 Cr2 O2– + – 3+ 7 + 14H + 6e ⇌ 2Cr + 7H2 O + 1,33 Cℓ2 (g) + 2e ⇌ 2Cℓ– – + 1,36 MnO–4 + 8H+ + 5e– ⇌ Mn2+ + 4H2 O + 1,51 H2 O2 + 2H+ + 2e– ⇌ 2H2 O + 1,77 Co3+ + e– ⇌ Co2+ + 1,81 F2 (g) + 2e– ⇌ 2F– + 2,87 Copyright reserved