Physical Sciences P2 Grade 11 Nov 2018 Eng_hlayiso.com_.pdf

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 11 PHYSICAL SCIENCES: CHEMISTRY (P2) NOVEMBER 2018 MARKS: 150 TIME: 3 hours This question paper consists of 12 pages, 4 data sheets and 1 answer sheet. Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 2 DBE/November 2018 CAPS – Grade 11 INSTRUCTIONS AND INFORMATION 1. Write your name and class (e.g. 11A) in the appropriate spaces on the ANSWER BOOK. 2. This question paper consists of TEN questions. Answer ALL the questions in the ANSWER BOOK except QUESTION 4.3 that must be answered on the attached ANSWER SHEET. 3. Hand in the ANSWER SHEET with the ANSWER BOOK. 4. Start EACH question on a NEW page in the ANSWER BOOK. 5. Number the answers correctly according to the numbering system used in this question paper. 6. Leave ONE line between two subquestions, e.g. between QUESTION 2.1 and QUESTION 2.2. 7. You may use a non-programmable calculator. 8. You may use appropriate mathematical instruments. 9. You are advised to use the attached DATA SHEETS. 10. Show ALL formulae and substitutions in ALL calculations. 11. Round off your FINAL numerical answers to a minimum of TWO decimal places. 12. Give brief motivations, discussions, etc. where required. 13. Write neatly and legibly. Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 3 DBE/November 2018 CAPS – Grade 11 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 1.10) in the ANSWER BOOK, e.g. 1.11 E. 1.1 The tendency of an atom to attract the bonding pair of electrons is known as … A electron affinity. B electronegativity. C polarity. D activation energy. (2) 1.2 Bond length is the average distance between the … A orbitals of two bonded atoms. B electrons in two bonded atoms. C nuclei of two bonded atoms. D molecules of the same substance. (2) 1.3 Hydrogen bonds and London forces (induced dipole forces) have a common characteristic in that they … A are both stronger than chemical bonds. B both occur between non-polar molecules. C both occur between polar molecules. D are both intermolecular forces. (2) 1.4 In order to double the volume of a fixed amount of moles of an enclosed gas, the temperature in … at constant pressure. A ºC can be doubled B K can be doubled C ºC can be halved D K can be halved (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 4 DBE/November 2018 CAPS – Grade 11 1.5 The graph that CORRECTLY represents the relationship between the pressure (kPa) and the temperature (K) of an enclosed gas at constant volume is … A p B p (kPa) (kPa) T (K) T (K) C D p p (kPa) (kPa) T (K) T (K) (2) 1.6 The solution that will have the greatest concentration of H+ ions if complete ionisation takes place, is … A 0,4 dm3 of a 1 mol·dm-3 H 2 SO 4 solution. B 0,4 dm3 of a 1 mol·dm-3 HCℓ solution. C 1 dm3 of a 1 mol·dm-3 HCℓ solution. D 0,4 dm3 of a 1 mol·dm-3 CH 3 COOH solution. (2) 1.7 Which ONE of the following is NOT a typical reaction of hydrochloric acid? A It neutralises a base with the release of hydrogen gas. B It forms hydronium ions in water. C It colours lithmus paper red. D It forms CO 2 when reacting with a metal carbonate. (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 5 DBE/November 2018 CAPS – Grade 11 1.8 Which ONE of the following pairs represents the conjugate acid and conjugate base of HPO 24− ? CONJUGATE ACID CONJUGATE BASE A PO 34− H2PO −4 B H2PO −4 PO 34− C H2PO −4 H3PO 4 D H2PO 24− PO 24− (2) 1.9 Which ONE of the following indicates the CORRECT colour of bromothymol blue in an acid and a base? BROMOTHYMOL BLUE BROMOTHYMOL BLUE IN AN ACID IN A BASE A Orange Yellow B Blue Red C Pink Colourless D Yellow Blue (2) 1.10 In which ONE of the following reactions is HCℓ oxidised? A HCℓ(aq) + H 2 O(ℓ) → H 3 O+(aq) + Cℓ-(aq) B CaCO 3 (s) + 2HCℓ(aq) → CaCℓ 2 (aq) + H 2 O(ℓ) + CO 2 (g) C NH 3 (aq) + HCℓ(aq) → NH 4 Cℓ(aq) D MnO 2 (aq) + 4HCℓ(aq) → MnCℓ 2 (aq) + H 2 O(ℓ) + Cℓ 2 (g) (2) [20] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 6 DBE/November 2018 CAPS – Grade 11 QUESTION 2 (Start on a new page.) Hydrogen cyanide (HCN) is a very poisonous compound used in the manufacturing of plastics, mining of gold and as a poison. 2.1 Define the term chemical bond. (2) 2.2 Draw Lewis structures for: 2.2.1 HCN (2) 2.2.2 H2O (2) 2.3 What is the shape of the HCN molecule? (1) 2.4 Calculate the electronegativity difference for the CN bond. (1) 2.5 What is polarity of the HCN molecule? Write only POLAR or NON-POLAR. (1) The table below indicates the values of the bond length and bond energy of the different bonds in HCN. BOND BOND LENGTH BOND ENERGY (nm) (kJ·mol-1) CH 0,109 413 CN 0,116 890 2.6 Explain why the bond energy of the CN bond is more than the bond energy of the CH bond. (2) 2.7 Explain the difference between the bond length of the CH bond and the bond length of the CN bond. (2) 2.8 Will HCN be soluble in water? Write only YES or NO. (1) 2.9 Explain the answer to QUESTION 2.8 by referring to the polarity and intermolecular forces of the compounds. (3) [17] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 7 DBE/November 2018 CAPS – Grade 11 QUESTION 3 (Start on a new page.) The reaction below is used in the Haber process to manufacture ammonia. N 2 (g) + 3H 2 (g) → 2NH 3 (g) The boiling points of the substances in the reaction are as follows: SUBSTANCE BOILING POINT (ºC) H2 -252,9 N2 -195,8 NH 3 -33,3 3.1 Refer to the intermolecular forces and explain the difference in boiling point between NH 3 and N 2 . (3) 3.2 Write down the FORMULA of the substance in the table that will have the lowest melting point. (1) 3.3 Explain why H 2 will evaporate faster than N 2 . Refer to the type and relative strength of the intermolecular forces. (3) 3.4 Write down the FORMULA of the substance in the table that will have the highest vapour pressure. Explain your answer. (3) [10] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 8 DBE/November 2018 CAPS – Grade 11 QUESTION 4 (Start on a new page.) A certain amount of gas is sealed in a container of which the volume can change. The relationship between the pressure and volume of the gas at 20 ºC is investigated. The results of the experiment are given in the table below. PRESSURE (kPa) VOLUME (dm3) 70 174 95 128 130 93,6 165 74 205 59 240 51 260 47 4.1 Name the gas law that is represented by the results of the experiment. (1) 4.2 Write down a hypothesis for the investigation. (2) 4.3 Draw a graph of volume versus pressure on the ANSWER SHEET attached. (3) 4.4 Calculate the volume of the gas at 300 kPa. (3) 4.5 When the volume of the gas is measured at 300 kPa, it is 44 dm3. Explain why the measured volume differs from the volume calculated in QUESTION 4.4. (2) 4.6 Which temperature condition will cause a gas to deviate from ideal behaviour? Write only HIGH or LOW. (1) 4.7 Explain the answer to QUESTION 4.6. (2) 4.8 Calculate the number of moles of the gas in the container at the INITIAL pressure and volume. (4) [18] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 9 DBE/November 2018 CAPS – Grade 11 QUESTION 5 (Start on a new page.) A balloon is filled with 160 g of argon gas (Ar). The pressure of the gas is 120 kPa at a temperature of 15 ºC. 5.1 Calculate the volume of the balloon. (4) 5.2 The temperature of the gas is now increased BY 20 ºC and the initial pressure is doubled. Calculate the new volume of the balloon. (4) [8] QUESTION 6 (Start on a new page.) 6.1 In an experiment, a learner added 1,5 g of sodium carbonate (Na 2 CO 3 ) to hydrochloric acid (HCℓ). A volume of 306 cm3 of carbon dioxide gas was formed and collected under standard pressure at room temperature. Take the molar gas volume at room temperature (V m ) as 24,45 dm3. The unbalanced equation for the reaction is: Na 2 CO 3 (s) + HCℓ(aq) → NaCℓ(aq) + H 2 O(ℓ) + CO 2 (g) 6.1.1 Define the term one mole of a substance. (2) 6.1.2 Balance the equation for the reaction. (2) 6.1.3 Calculate the mass of sodium carbonate that reacted. (7) 6.1.4 Calculate the percentage of sodium carbonate in excess. (2) 6.2 Zinc reacts with sulphuric acid according to the reaction below. Zn(s) + H 2 SO 4 (aq) → ZnSO 4 (aq) + H 2 (g) The mass of zinc is recorded during the experiment and is shown on the graph below. The reaction stops after 2 minutes. 5 Mass of Zn (g) 2 Time (min) 1 2 3 6.2.1 Name the substance that is the limiting reagent. (1) 6.2.2 Calculate the initial concentration of the sulphuric acid if 50 cm3 of the acid was used. (5) [19] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 10 DBE/November 2018 CAPS – Grade 11 QUESTION 7 (Start on a new page.) The following reaction between ammonia and oxygen takes place in a closed system at constant pressure and temperature: 4NH 3 (g) + 5O 2 (g) → 4NO(g) + 6H 2 O(g) 2 670 Ep (kJ.mol-1) Ea 400 ∆H 183,3 Course of reaction 7.1 Define the term activation energy. (2) 7.2 Give a reason why this reaction is exothermic. (1) 7.3 Calculate the heat of reaction. (3) 7.4 Redraw the graph and indicate with a dotted line the effect of a catalyst on the activation energy. (2) 7.5 State Avogadro's law in words. (2) 7.6 If 6 dm3 of NH 3 and 9 dm3 of O 2 are used, calculate the TOTAL VOLUME of the gases at the end of the reaction. (4) 7.7 The reaction above is the first step in the manufacturing of an acid. This acid contains 1,59% hydrogen, 22,2% nitrogen and 76,2% oxygen. Determine the empirical formula of the acid. (5) [19] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 11 DBE/November 2018 CAPS – Grade 11 QUESTION 8 (Start on a new page.) Ammonia can readily dissolve in water according to the equation below: - NH 3 (g) + H 2 O(ℓ) → NH +4 (aq) + OH (aq) 8.1 Explain why a hydroxide ion is regarded as a Lowry-Brønsted base. (2) 8.2 Identify the type of bond responsible for the formation of the ammonium ion in the above equation. (1) 8.3 Write a balanced equation to show how the ampholyte in the above equation will act as a base when it reacts with hydrochloric acid (HCℓ). (2) 5 dm3 of nitric acid (HNO 3 ), with a concentration of 0,75 mol·dm-3, is spilled accidentally in a small pond of water. The acid and water has a total volume of 1 000 dm3. To neutralise the acid, calcium hydroxide is added to the water. 2HNO 3 (aq) + Ca(OH) 2 (aq) → Ca(NO 3 ) 2 (aq) + 2H 2 O(ℓ) 8.4 Define the term concentration. (2) 8.5 Calculate the concentration of the acid AFTER it was spilled in the pond. (4) 8.6 Use calculations to determine if 120 g of calcium hydroxide will be sufficient to react completely with ALL the acid in the pond. (6) [17] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 12 DBE/November 2018 CAPS – Grade 11 QUESTION 9 (Start on a new page.) The reaction between permanganate ions ( MnO −4 ) and hydrogen sulphide (H 2 S) is given below. MnO −4 (aq) + H+(aq) + H 2 S(g) → Mn2+(aq) + S(s) + H 2 O(ℓ) 9.1 Define reduction in terms of oxidation numbers. (2) 9.2 Determine the oxidation number of manganese in the permanganate ion. (1) 9.3 Write down the FORMULA of the substance that undergoes oxidation. (1) 9.4 Explain the answer to QUESTION 9.3 in terms of oxidation numbers. (2) 9.5 Write down the FORMULA for the oxidising agent. (1) 9.6 Write down the oxidation half-reaction. (2) 9.7 Use the ion-electron method and write down the balanced net ionic equation. (3) [12] QUESTION 10 (Start on a new page.) Gold and iron extraction are important mining processes in South Africa. Refining takes place according to the following reactions: - Gold is dissolved using cyanide ions (CN ) to extract it from the ore: 4Au(s) + 8NaCN(aq) + 2H 2 O(ℓ) + O 2 (g) → 4NaAu(CN) 2 (aq) + 4NaOH(aq) Iron(lll)oxide is burned in a furnace in the presence of CO: Fe 2 O 3 (s) + 3CO(s) → 2Fe(ℓ) + 3CO 2 (g) 10.1 Name TWO disadvantages of deep-shaft mining in comparison with open- cast mining. (2) 10.2 Write down the FORMULA of the substance that is reduced in the reaction used to extract gold. (1) 10.3 Use oxidation numbers to explain how you arrived at the answer to QUESTION 10.2. (1) 10.4 Write the reduction half-reaction for the iron extraction reaction. (2) 10.5 Calculate the percentage of iron present in Fe 2 O 3 . (2) 10.6 Only 65% of the ore contains iron. If 2 500 kg of ore is used, calculate the mass of iron that can be extracted from the ore. (2) [10] TOTAL: 150 Copyright reserved

Downloaded from hlayiso.com Physical Sciences/P2 1 DBE/November 2018 CAPS – Grade 11 DATA FOR PHYSICAL SCIENCES GRADE 11 PAPER 2 (CHEMISTRY) GEGEWENS VIR FISIESE WETENSKAPPE GRAAD 11 VRAESTEL 2 (CHEMIE) TABLE 1: PHYSICAL CONSTANTS/TABEL 1: FISIESE KONSTANTES NAME/NAAM SYMBOL/SIMBOOL VALUE/WAARDE Avogadro's constant NA 6,02 x 1023 mol-1 Avogadro-konstante Molar gas constant R 8,31 J∙K-1∙mol-1 Molêre gaskonstante Standard pressure pθ 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 TABLE 2: FORMULAE/TABEL 2: FORMULES p1V1 p 2 V2 = pV = nRT T1 T2 m N n= n= M NA V n m n= c= OR/OF c= Vm V MV Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 2 DBE/November 2018 CAPS – Grade 11 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) 1 Atomic number 2 KEY/SLEUTEL Atoomgetal 2,1 H He 1 4 3 4 29 5 6 7 8 9 10 Electronegativity Symbol 1,0 Li 1,5 Be Elektronegatiwiteit 1,9 Cu Simbool 2,0 B 2,5 C 3,0 N 3,5 O 4,0 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 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/November 2018 CAPS – Grade 11 TABLE 4A: STANDARD REDUCTION POTENTIALS TABEL 4A: STANDAARD-REDUKSIEPOTENSIALE θ Half-reactions/Halfreaksies E (V) F 2 (g) + 2e− ⇌ 2F− + 2,87 3+ 2+ Co + e− ⇌ Co + 1,81 + H 2 O 2 + 2H +2e− ⇌ 2H 2 O +1,77 − + 2+ MnO 4 + 8H + 5e− ⇌ Mn + 4H 2 O + 1,51 Cℓ 2 (g) + 2e− ⇌ 2Cℓ− + 1,36 2− + 3+ Cr 2 O 7 + 14H + 6e− ⇌ 2Cr + 7H 2 O + 1,33 + − O 2 (g) + 4H + 4e ⇌ 2H 2 O + 1,23 + 2+ MnO 2 + 4H + 2e− ⇌ Mn + 2H 2 O + 1,23 2+ Pt + 2e− ⇌ Pt + 1,20 Br 2 (ℓ) + 2e− ⇌ 2Br− + 1,07 − + NO 3 + 4H + 3e− ⇌ NO(g) + 2H 2 O + 0,96 Increasing reducing ability/Toenemende reduserende vermoë 2+ − Hg + 2e ⇌ Hg(ℓ) + 0,85 + Ag + e− ⇌ Ag + 0,80 Increasing oxidising ability/Toenemende oksiderende vermoë − + NO 3 + 2H + e− ⇌ NO 2 (g) + H 2 O + 0,80 3+ − 2+ Fe + e ⇌ Fe + 0,77 + O 2 (g) + 2H + 2e− ⇌ H2O2 + 0,68 I 2 + 2e− ⇌ 2I− + 0,54 + Cu + e− ⇌ Cu + 0,52 + SO 2 + 4H + 4e− ⇌ S + 2H 2 O + 0,45 2H 2 O + O 2 + 4e− ⇌ 4OH− + 0,40 2+ Cu + 2e− ⇌ Cu + 0,34 2− + SO 4 + 4H + 2e− ⇌ SO 2 (g) + 2H 2 O + 0,17 2+ + Cu + e− ⇌ Cu + 0,16 4+ 2+ Sn + 2e− ⇌ Sn + 0,15 + S + 2H + 2e− ⇌ H 2 S(g) + 0,14 + 2H + 2e− ⇌ H 2 (g) 0,00 3+ Fe + 3e− ⇌ Fe − 0,06 2+ Pb + 2e− ⇌ Pb − 0,13 2+ Sn + 2e− ⇌ Sn − 0,14 2+ Ni + 2e− ⇌ Ni − 0,27 2+ Co + 2e− ⇌ Co − 0,28 2+ Cd + 2e− ⇌ Cd − 0,40 3+ 2+ Cr + e− ⇌ Cr − 0,41 2+ Fe + 2e− ⇌ Fe − 0,44 3+ Cr + 3e− ⇌ Cr − 0,74 2+ Zn + 2e− ⇌ Zn − 0,76 2H 2 O + 2e− ⇌ H 2 (g) + 2OH− − 0,83 2+ Cr + 2e− ⇌ Cr − 0,91 2+ Mn + 2e− ⇌ Mn − 1,18 3+ Aℓ + 3e− ⇌ Aℓ − 1,66 2+ Mg + 2e− ⇌ Mg − 2,36 + Na + e− ⇌ Na − 2,71 2+ Ca + 2e− ⇌ Ca − 2,87 2+ Sr + 2e− ⇌ Sr − 2,89 2+ Ba + 2e− ⇌ Ba − 2,90 + - Cs + e ⇌ Cs - 2,92 + − K +e ⇌ K − 2,93 + Li + e− ⇌ Li − 3,05 Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 4 DBE/November 2018 CAPS – Grade 11 TABLE 4B: STANDARD REDUCTION POTENTIALS TABEL 4B: STANDAARD-REDUKSIEPOTENSIALE θ Half-reactions/Halfreaksies E (V) + Li + e− ⇌ Li − 3,05 + K + e− ⇌ K − 2,93 + Cs + e− ⇌ Cs − 2,92 2+ Ba + 2e− ⇌ Ba − 2,90 2+ Sr + 2e− ⇌ Sr − 2,89 2+ Ca + 2e− ⇌ Ca − 2,87 + Na + e− ⇌ Na − 2,71 2+ Mg + 2e− ⇌ Mg − 2,36 3+ Aℓ + 3e− ⇌ Aℓ − 1,66 2+ Mn + 2e− ⇌ Mn − 1,18 2+ Cr + 2e− ⇌ Cr − 0,91 2H 2 O + 2e− ⇌ H 2 (g) + 2OH− − 0,83 2+ Zn + 2e− ⇌ Zn − 0,76 3+ Cr + 3e− Cr Increasing oxidising ability/Toenemende oksiderende vermoë ⇌ − 0,74 2+ Fe + 2e− ⇌ Fe − 0,44 3+ 2+ Cr + e− ⇌ Cr − 0,41 Increasing reducing ability/Toenemende reduserende vermoë 2+ Cd + 2e− ⇌ Cd − 0,40 2+ Co + 2e− ⇌ Co − 0,28 2+ Ni + 2e− ⇌ Ni − 0,27 2+ Sn + 2e− ⇌ Sn − 0,14 2+ Pb + 2e− ⇌ Pb − 0,13 3+ Fe + 3e− ⇌ Fe − 0,06 + 2H + 2e− ⇌ H 2 (g) 0,00 + S + 2H + 2e− ⇌ H 2 S(g) + 0,14 4+ 2+ Sn + 2e− ⇌ Sn + 0,15 2+ + Cu + e− ⇌ Cu + 0,16 2− + SO 4 + 4H + 2e− ⇌ SO 2 (g) + 2H 2 O + 0,17 2+ − Cu + 2e ⇌ Cu + 0,34 2H 2 O + O 2 + 4e− ⇌ 4OH− + 0,40 + SO 2 + 4H + 4e− ⇌ S + 2H 2 O + 0,45 + Cu + e− ⇌ Cu + 0,52 I 2 + 2e− ⇌ 2I− + 0,54 + O 2 (g) + 2H + 2e− ⇌ H2O2 + 0,68 3+ 2+ Fe + e− ⇌ Fe + 0,77 − + NO 3 + 2H + e− ⇌ NO 2 (g) + H 2 O + 0,80 + − Ag + e ⇌ Ag + 0,80 2+ Hg + 2e− ⇌ Hg(ℓ) + 0,85 − + NO 3 + 4H + 3e− ⇌ NO(g) + 2H 2 O + 0,96 − − Br 2 (ℓ) + 2e ⇌ 2Br + 1,07 2+ Pt + 2 e− ⇌ Pt + 1,20 + 2+ MnO 2 + 4H + 2e− ⇌ Mn + 2H 2 O + 1,23 + O 2 (g) + 4H + 4e− ⇌ 2H 2 O + 1,23 2− + 3+ Cr 2 O 7 + 14H + 6e− ⇌ 2Cr + 7H 2 O + 1,33 − − Cℓ 2 (g) + 2e ⇌ 2Cℓ + 1,36 − + 2+ MnO 4 + 8H + 5e− ⇌ Mn + 4H 2 O + 1,51 + H 2 O 2 + 2H +2 e− ⇌ 2H 2 O +1,77 3+ 2+ Co + e− ⇌ Co + 1,81 F 2 (g) + 2e− ⇌ 2F − + 2,87 Copyright reserved

Downloaded from hlayiso.com Physical Sciences/P2 DBE/November 2018 CAPS – Grade 11 ANSWER SHEET SUBMIT THIS SHEET WITH THE ANSWER BOOK. NAME ______________________________________________________CLASS____ QUESTION 4.3 Graph of volume versus pressure Volume (dm3) Pressure (kPa) Copyright reserved