Physical Sciences P2 Grade 11 Nov 2017 Eng_hlayiso.com_.pdf

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 11 PHYSICAL SCIENCES: CHEMISTRY (P2) NOVEMBER 2017 MARKS: 150 TIME: 3 hours This question paper consists of 11 pages, 4 data sheets and 1 answer sheet. Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 2 DBE/November 2017 CAPS – Grade 11 INSTRUCTIONS AND INFORMATION 1. Write your name and class (for example 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 4.1, which must be answered on the attached ANSWER SHEET. 3. Hand in the ANSWER SHEET together 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, for example 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 et cetera where required. 13. Write neatly and legibly. Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 3 DBE/November 2017 CAPS – Grade 11 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 number (1.1–1.10) in the ANSWER BOOK, for example 1.11 E. 1.1 Which ONE of the bonds between the atoms below has the highest polarity? A H-C B H - Cℓ C H-O D H-N (2) 1.2 Solid iodine sublimes easily. The intermolecular forces present in iodine are … A London forces. B hydrogen bonding. C ion-dipole forces. D dipole-dipole forces. (2) 1.3 The graph below shows how the potential energy varies with distance between the nuclei of two nitrogen atoms when a double bond between the nitrogen atoms (N = N) is formed. Potential energy (kJ∙mol-1) 0 L l l l l Distance between 120 125 130 135 140 nuclei (pm) -100 -418 Choose from the table the bond length and bond energy for N = N. BOND LENGTH BOND ENERGY (pm) (kJ∙mol-1) A 120 0 B 125 518 C 125 418 D 130 -100 (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 4 DBE/November 2017 CAPS – Grade 11 1.4 According to Boyle's law, … 1 A pα if T is constant. V B V α T if p is constant. 1 C Vα if p is constant. T D p α V if n is constant. (2) 1.5 One mole of any gas occupies the same volume at the same temperature and pressure. This statement is known as … A Charles's law. B Gay Lussac's law. C Avogadro's law. D the ideal gas LAW. (2) 1.6 One mole of a gas, SEALED in a container, has volume V at temperature T and pressure p. If the pressure is increased to 3p, the ratio between the volume and temperature (V : T) is … A 1:⅓ B 3:1 C ⅓:3 D 1:3 1.7 The chemical equation that represents an endothermic reaction: A NH 4 NO 3 (s) + H 2 O(ℓ) → NH 4 +(aq) + NO 3 -(aq) ∆H > 0 B 2Mg(s) + O 2 (g) → 2MgO(s) ∆H < 0 C Zn(s) + 2HCℓ(aq) → ZnCℓ 2 (aq) + H 2 (g) + heat D H 2 (g) + Cℓ 2 (g) → 2HCℓ(g) ∆H = -131 kJ∙mol-1 (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 5 DBE/November 2017 CAPS – Grade 11 1.8 The CORRECT formula for nitric acid: A H 2 SO 4 B CH 3 COOH C NH 3 D HNO 3 (2) 1.9 Consider the reaction below. Zn(s) + CuSO 4 (aq) → ZnSO 4 (aq) + Cu(s) Which substance is the oxidising agent? A Zn B Cu 2+ C Zn 2+ D Cu (2) 1.10 Which ONE of the reactions below will produce the salt sodium ethanoate (sodium acetate)? A HCℓ(s) + CH 3 COOH(aq) → B CH 3 COOH(aq) + H 2 O(ℓ) → C CH 3 COOH(aq) + NaOH(aq) → D H 2 CO 3 (aq) + NaOH(aq) → (2) [20] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 6 DBE/November 2017 CAPS – Grade 11 QUESTION 2 (Start on a new page.) Consider the following two reactions of methane (CH 4 ): Reaction 1: CH 4 (g) + HCℓ (g) → CH 3 Cℓ (g) + H 2 (g) Reaction 2: CH 4 (g) + 2O 2 (g) → CO 2 (g) + 2H 2 O (g) 2.1 Define the term covalent bond. (2) 2.2 Draw Lewis structures for: 2.2.1 CH 3 Cℓ (2) 2.2.2 CO 2 (2) 2.3 How many lone-pair electrons are on the central atom in the CO 2 molecule? (1) 2.4 Identify ONE of the substances in Reaction 2 that can form a dative covalent bond when reacting with an acid. (1) 2.5 Write down the shape of the: 2.5.1 H 2 O molecule (1) 2.5.2 CO 2 molecule (1) 2.6 Although the molecules of CH 4 and CH 3 Cℓ have the same shape, CH 4 is non-polar, while CH 3 Cℓ is polar. Give a reason for the difference in molecular polarity. (1) [11] QUESTION 3 (Start on a new page.) Consider the list of six substances with their formulae and boiling points in the table below. NAME OF SUBSTANCE FORMULA BOILING POINT (°C) Water H2O 100 Ethanol CH 3 CH 2 OH 78 Bromine Br 2 58,8 Iodine I2 184,3 Ammonia NH 3 -33,3 Phosphine PH 3 -87,7 3.1 Explain why ethanol is soluble in water. Refer to the relative strength of the intermolecular forces in ethanol and water. (3) 3.2 Explain why the boiling point of iodine is higher than that of bromine. Refer to the intermolecular forces present in EACH substance in the explanation. (3) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 7 DBE/November 2017 CAPS – Grade 11 3.3 Explain why phosphine will evaporate faster than ammonia by referring to the types of intermolecular forces present in EACH substance. (4) 3.4 Water, ethanol and bromine are all liquids at room temperature. Which ONE will have the highest vapour pressure? (1) 3.5 Give a reason for the answer to QUESTION 3.4 by referring to the relative strength of the intermolecular forces and boiling points. (2) [13] QUESTION 4 (Start on a new page.) In an experiment to investigate the relationship between pressure and temperature of an enclosed gas, 48 g of oxygen gas was sealed in a container. The results obtained are recorded in the table below. PRESSURE (kPa) TEMPERATURE (K) 155,8 250 187,0 300 218,1 350 249,3 400 280,5 450 4.1 Draw a graph of pressure versus temperature on the attached ANSWER SHEET. Extrapolate the graph so that it intersects the y-axis. (4) 4.2 What conclusion can be made from the final graph? (2) 4.3 Explain why it will not be possible to obtain accurate values at very low temperatures. (2) 4.4 Use the kinetic molecular theory to explain the effect of an increase in temperature on the pressure of a gas. (4) 4.5 Under which conditions of temperature and pressure will a real gas act as an ideal gas? (2) 4.6 Calculate the gradient of the graph. (3) 4.7 Use the answer to QUESTION 4.6 to determine the volume of the container. (5) [22] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 8 DBE/November 2017 CAPS – Grade 11 QUESTION 5 (Start on a new page.) Weather balloons are sent into space to gather data. The balloons usually burst at a pressure of 27 640 Pa and a volume of 36,3 m3. The data collector then falls back to Earth. balloon data collector The gas in a certain weather balloon has an initial volume of 12,6 m3 and pressure of 105 000 Pa at a temperature of 25 °C when it is released into space. Calculate the: 5.1 Temperature of the gas, in °C, in the balloon when it bursts (4) 5.2 Initial amount of gas (in moles) in the balloon (4) [8] QUESTION 6 (Start on a new page.) 6.1 The decomposition of hydrogen peroxide in the presence of a catalyst at standard pressure and room temperature is given by the unbalanced chemical equation below. H 2 O 2 (aq) → H 2 O(ℓ) + O 2 (g) The oxygen gas is collected and the volume is recorded over a period of time. The reaction is completed at time t. The results are plotted on a graph of volume O 2 versus time, as shown below. 600 Volume O2 (cm ) 3 Time (s) t Take the molar gas volume (V m ) as 24,45 dm3 at room temperature and standard pressure. 6.1.1 Balance the equation. (2) 6.1.2 How would a catalyst affect the reaction? (2) 6.1.3 Use the information on the graph to calculate the mass of hydrogen peroxide that decomposed. (6) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 9 DBE/November 2017 CAPS – Grade 11 6.2 In an experiment, a learner adds 500 cm3 hydrochloric acid (HCℓ), with a concentration of 0,36 mol·dm-3, to 1,2 g of magnesium in a test tube. She records the change in the mass of magnesium as the reaction proceeds at regular intervals. The balanced chemical equation for the reaction is: Mg(s) + 2HCℓ(aq) → MgCℓ 2 (aq) + H 2 (g) The change in the mass of magnesium during the reaction is shown on the graph below. 1,2 Magnesium (g) Time (min.) 1 2 3 6.2.1 Identify the limiting agent in this reaction. Give a reason for the answer. (2) 6.2.2 Calculate the number of moles of unreacted hydrochloric acid in the test tube after 3 minutes. (7) [19] QUESTION 7 (Start on a new page.) The equation for the combustion of butane gas is given below. butane(g) + 13O 2 (g) → 8CO 2 (g) + 10H 2 O(g) ∆H < 0 7.1 Define the term activation energy. (2) 7.2 Is the combustion reaction of butane exothermic or endothermic? Give a reason for the answer. (2) 7.3 Draw a sketch graph of potential energy versus course of reaction for the reaction above. Clearly indicate the following on the graph: • Activation energy • Heat of reaction (∆H) • Reactants and products (3) 7.4 Determine the empirical formula of butane gas if it consists of 82,76% carbon and 17,24% hydrogen. (4) [11] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 10 DBE/November 2017 CAPS – Grade 11 QUESTION 8 (Start on a new page.) 8.1 Two reactions of sulphuric acid are shown in the diagram below. Reaction 1 H2SO4 Salt X + Product Y NaOH Reaction 2 H2O Ampholyte A + H3O+ 8.1.1 Define a Lowry-Brønsted base. (2) 8.1.2 Write down a balanced equation for Reaction 1. (3) 8.1.3 Write down the NAME of the salt represented by X. (2) 8.1.4 Write down the FORMULA of ampholyte A. (2) 8.1.5 Write down the formulae of the TWO conjugate acid-base pairs in Reaction 2. (4) 8.2 A solution of sodium hydroxide (NaOH) is prepared by dissolving 6 g solid NaOH in 500 cm3 water. This solution reacts completely with 10 g impure ammonium chloride (NH 4 Cℓ) according to the equation below. NaOH(aq) + NH 4 Cℓ(s) → NaCℓ(aq) + H 2 O(ℓ) + NH 3 (aq) 8.2.1 Calculate the concentration of the NaOH solution. (4) 8.2.2 Calculate the percentage impurities in the NH 4 Cℓ. (6) [23] QUESTION 9 (Start on a new page.) The reaction between dichromate ions (Cr 2 O 7 -2) and iron(II) ions (Fe2+) in an acidic medium is given below. Cr 2 O 7 -2(aq) + Fe2+(aq) + H+(aq) → Cr3+(aq) + Fe3+(aq) + H 2 O(ℓ) 9.1 Determine the oxidation number of CHROMIUM in Cr 2 O 7 -2(aq). (2) 9.2 Define reduction in terms of electron transfer. (2) 9.3 Write down the FORMULA of the substance that undergoes oxidation. Explain the answer in terms of oxidation numbers. (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 11 DBE/November 2017 CAPS – Grade 11 9.4 Write down the FORMULA of the oxidising agent. (2) 9.5 Write down the reduction half-reaction. (2) 9.6 Write down the net balanced ionic equation for the reaction, using the ion-electron method. (3) [13] QUESTION 10 (Start on a new page.) Gold and iron are two of many minerals mined in South Africa. Iron is mined in open-cast mines, while gold is usually found in deep-shaft (underground) mines. During the process of refining, the following chemical reactions take place to extract the metal from the ore: Gold is dissolved in a solution containing cyanide ions (CN-) to extract it from the ore. The balanced chemical equation for the reaction is: 4Au(s) + 8NaCN(aq) + 2H 2 O(ℓ) + O 2 (g) → 4NaAu(CN) 2 (aq) + NaOH(aq) Iron(Vl) oxide and carbon are heated in a furnace to extract iron from the ore. The balanced chemical equation for the reaction is: 2Fe 2 O 3 (s) +3C(s) → 4Fe(ℓ) + 3CO 2 (g) 10.1 State TWO advantages of open-cast mining when compared to deep-shaft (underground) mining. (2) Consider the iron extraction reaction. 10.2 Is iron oxidised or reduced during the reaction? Give a reason for the answer. (2) 10.3 State TWO disadvantages of using carbon in this reaction. (2) Consider the gold extraction reaction. 10.4 Give ONE reason why gold is present as an element in the ore. (2) 10.5 What role does oxygen gas (O 2 ) play in the reaction? (2) [10] TOTAL: 150 Copyright reserved

Downloaded from hlayiso.com Physical Sciences/P2 1 DBE/November 2017 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 2017 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 2017 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 2017 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 Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 DBE/November 2017 CAPS – Grade 11 ANSWER SHEET Hand in this ANSWER SHEET together with the ANSWER BOOK. NAME: _____________________________________ CLASS:_____ QUESTION 4.1 GRAPH OF PRESSURE VERSUS TEMPERATURE Pressure (kPa) Copyright reserved Temperature (K)