Gr 11 Physical Sciences P2 (English) June 2024 Question Paper_hlayiso.com_.pdf

Downloaded from hlayiso.com PROVINCIAL EXAMINATION JUNE 2024 GRADE 11 PHYSICAL SCIENCES: CHEMISTRY PAPER 2 TIME: 1 hour MARKS: 50 6 pages + 2 data sheets P.T.O.

Downloaded from hlayiso.com PHYSICAL SCIENCES: CHEMISTRY 2 (PAPER 2) GRADE 11 INSTRUCTIONS AND INFORMATION: 1. Write your name in the appropriate space on the ANSWER BOOK. 2. This question paper consists of FOUR questions. Answer ALL 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. You are advised to use the attached DATA SHEETS. 9. Show ALL formulae and substitutions in ALL calculations. 10. Round-off your FINAL numerical answers to a minimum of TWO decimal places. 11. Give brief motivations, discussions, et cetera where required. 12. Write neatly and legibly. P.T.O.

Downloaded from hlayiso.com PHYSICAL SCIENCES: CHEMISTRY 3 (PAPER 2) GRADE 11 QUESTION 1: MULTIPLE-CHOICE QUESTIONS Four options are provided as possible answers to the following questions. Each question has only ONE correct answer. Write only the letter (A – D) next to the question numbers (1.1 – 1.4) in the ANSWER BOOK, e.g. 1.5 A. 1.1 A dative covalent bond forms when… A water decomposes. B ionic compounds dissociate in water. C hydronium ions are produced. D hydroxide ions are produced. (2) 1.2 The factor that does NOT affect bond length between two atoms is: A The size of the atoms. B The difference in electronegativity between the atoms. C The number of bonds between the atoms. D The valences of the atoms. (2) 1.3 Identify the intermolecular force that must be overcome to convert the following substance from a liquid to a gas: CH3OH A London Forces B Dipole-dipole forces C Hydrogen bonds D Ionic bonds (2) 1.4 Which of the following groups of substances have the same intermolecular forces present? A NH3, CH3Cℓ B CH4, CO2 C H2O, CO D HCℓ, H2O (2) [8] P.T.O.

Downloaded from hlayiso.com PHYSICAL SCIENCES: CHEMISTRY 4 (PAPER 2) GRADE 11 QUESTION 2 (Start on a new page.) 2.1 Ammonia (NH3) is a colourless, poisonous gas. It is synthesized by the Haber-Bosch process, in which nitrogen gas and hydrogen gas are reacted at high temperature and pressure. Ammonia has a lone pair. 2.1.1 Define the term lone pair. (2) 2.1.2 Name and explain the type of chemical bond between nitrogen and hydrogen. (3) 2.1.3 Draw the Lewis structure for the ammonia molecule. (2) 2.1.4 Name the shape of the ammonia molecule. (2) 2.2 Ammonia reacts with a hydrogen ion to form NH4+ . 2.2.1 How many electrons surround the central atom in NH4+ ? (2) 2.2.2 Name the type of bond between ammonia and hydrogen ions in NH4+ . (2) 2.3 Phosphine (PH3) and Ammonia (NH3) are molecules that have the same shape. Explain why the boiling point of PH3 is less than that of NH3. (3) [16] QUESTION 3 (Start on a new page.) The diagram below represents the bonding that takes place in a molecule. O X O The electronegativity difference between element X and oxygen is 1,0. 3.1 Define the term electronegativity. (2) 3.2 To which group in the periodic table does element X belong? Give a reason for your answer. (2) 3.3 Identify element X. (1) P.T.O.

Downloaded from hlayiso.com PHYSICAL SCIENCES: CHEMISTRY 5 (PAPER 2) GRADE 11 3.4 Is the molecule XO2 polar or non-polar? Explain your answer fully. Use the table below to answer the questions that follow. BOND BOND ENERGY BOND LENGTH (k.J.mol-1) O–H 463 96 N–H 389 100,8 C–C 348 154 (2) 3.5 Define the term bond energy. (2) 3.6 From the data provided, what is the relationship between bond length and bond energy? (2) [11] QUESTION 4 (Start on a new page.) The graph below shows the boiling points of different substances from groups 15 and 16 on the periodic table. H2O Boiling point (K) H2Te H2Se H2S Period 4.1 Define the term boiling point in words. (2) 4.2 Explain, in terms of the strengths of intermolecular forces, why the boiling points of H2O and NH3 are much higher than those of the rest of group 15 and 16. (3) P.T.O.

Downloaded from hlayiso.com PHYSICAL SCIENCES: CHEMISTRY 6 (PAPER 2) GRADE 11 4.3 The boiling points increase from H2S to H2Te. 4.3.1 Identify the strongest type of intermolecular forces present. (1) 4.3.2 Explain the trend that can be seen in their boiling points. (2) 4.3.3 Give the formula of one of the above mentioned compounds that will be a liquid at 0 °C? (1) 4.4 In the laboratory you are provided with the following chemicals: Cℓ2, SO2 and NaBr 4.4.1 Identify the intermolecular forces in each of the above compounds. (3) 4.4.2 Which ONE of the above chemicals will have the highest vapour pressure? Explain the answer. (3) [15] TOTAL: 50 END

Downloaded from hlayiso.com PHYSICAL SCIENCES: CHEMISTRY 7 (PAPER 2) 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 se konstante Molar gas constant R 8,31 J∙K-1∙mol-1 Molêre gaskonstante 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 T 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

Downloaded from hlayiso.com PHYSICAL SCIENCES: CHEMISTRY 8 (PAPER 2) 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 Fe 1,8 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 Tc 1,9 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