Physical Sciences Grade 10 P2 National November 2017 QP

Downloaded from hlayiso.com NATIONAL SENIOR CERTIFICATE GRADE 10 PHYSICAL SCIENCES: CHEMISTRY (P2) NOVEMBER 2017 MARKS: 150 TIME: 2 hours This question paper consists of 13 pages and 2 data sheets. Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 2 DBE/November 2017 CAPS – Grade 10 INSTRUCTIONS AND INFORMATION 1. Write your name and class (for example 10A) 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, for example 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. Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 3 DBE/November 2017 CAPS – Grade 10 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 Air can be classified as a/an … A element. B compound. C homogenous mixture. D heterogeneous mixture. (2) 1.2 The graph below shows the heating curve of a substance. Temperature (°C) C D 100 A B Time (s) In which part(s) of the graph does the substance gain kinetic energy? A BC only B CD only C AB and CD D AB, BC and CD (2) 1.3 In which ratio will group (I) elements react with group (VI) elements? A 2:1 B 1:6 C 6:1 D 1:3 (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 4 DBE/November 2017 CAPS – Grade 10 1.4 What is the total number of nucleons in the ion of calcium when calcium loses two electrons to form Ca2+? A 40 B 18 C 22 D 20 (2) 1.5 Which ONE of the following groups of elements shows the CORRECT trend of the density of metals? A Rb < K < Na < Li B K < Na < Li < Rb C Li < Na < K < Rb D Na < Li <Rb < K (2) 1.6 A learner used the flow chart below to classify some examples of substances P, Q and R. Yes Substance Definite shape P (P, Q, R) No Yes Definite volume Q No R What could substances P, Q and R possibly be? P Q R A Marble Oil Oxygen B Oil Marble Oxygen C Oxygen Oil Marble D Oxygen Marble Oil (2) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 5 DBE/November 2017 CAPS – Grade 10 1.7 In a 20 g sample of molecules, which sample below has the greatest number of moles? A NH 3 B N2 C CO 2 D H2 (2) 1.8 Carbon dioxide can change directly from the solid phase to the gas phase. This process is known as … A sublimation. B evaporation. C decomposition. D melting. (2) 1.9 The chemical name for Fe 2 (SO 4 ) 3 is … A iron sulphite. B iron(III) sulphate. C iron(II) sulphate. D iron sulphide. (2) 1.10 All the soil on Earth is known as the … A atmosphere. B biosphere. C lithosphere. D hydrosphere. (2) [20] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 6 DBE/November 2017 CAPS – Grade 10 QUESTION 2 (Start on a new page.) Consider the following substances: C 90 ; NaCℓ; CO 2 ; Fe; H2O 2.1 Write down a substance from the list above that is the following: 2.1.1 A molecular structure (1) 2.1.2 A metallic structure (1) 2.1.3 A covalent network structure (1) 2.1.4 An ionic network structure (1) 2.2 Draw the Lewis dot diagram for the CO 2 molecule. (2) 2.3 Identify the type of chemical bond in H 2 O. (1) 2.4 Draw the Lewis dot diagrams to show the formation of NaCℓ. (3) 2.5 Study the models of compounds A, B and C below and answer the questions that follow. A B C K+ I- K+ I- H H I- K+ I- K+ C N K+ I- K+ I- H H H H H Write down the: 2.5.1 Chemical name of compound A (1) 2.5.2 Chemical formula of compound B (1) 2.5.3 Common name of compound C (1) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 7 DBE/November 2017 CAPS – Grade 10 2.6 Many of the gases in air are very useful. An important industrial process, fractional distillation of liquid air, separates these gases from one another. Consider the diagram below and answer the questions that follow. Boils at -196 °C NITROGEN Compressed AIR LIQUID AIR Boils at -186 °C ARGON Boils at -183 °C OXYGEN 2.6.1 Is this separation process physical or chemical? (1) 2.6.2 Which physical property is used to separate the gases after they have been liquefied? (1) 2.6.3 Which gas has the weakest intermolecular forces? Explain the answer. (2) 2.7 State how EACH of the following changes when liquid nitrogen changes into gaseous nitrogen. Write down only INCREASE, DECREASE or REMAIN THE SAME. 2.7.1 Spaces between the particles (1) 2.7.2 Strength of the forces between the particles (1) 2.7.3 Energy of the particles (1) [20] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 8 DBE/November 2017 CAPS – Grade 10 QUESTION 3 (Start on a new page.) Consider the graph of the first ionisation energy and answer the questions that follow. 3.1 Define the term ionisation energy. (2) 3.2 State the general trend in ionisation energy from left to right across a period on the periodic table. (2) 3.3 There is a drop in ionisation energy from beryllium to boron. 3.3.1 Write down the sp-notation for beryllium AND boron. (4) 3.3.2 Explain this drop in ionisation energy. (3) 3.4 Is the following statement TRUE or FALSE? If false, rewrite the statement correctly. The ionisation energy of noble gases is high because of the half-filled s- and p-orbitals. (2) 3.5 Study the ionisation energy of the group (I) elements in the graph above and answer the questions that follow. 3.5.1 Give the general name of the group (I) elements. (1) 3.5.2 State the trend in the reactivity of elements in group (I). (2) 3.5.3 Explain the reason for the trend in QUESTION 3.5.2 by using the graph of ionisation energy. (2) [18] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 9 DBE/November 2017 CAPS – Grade 10 QUESTION 4 (Start on a new page.) 4.1 A certain element, X, has two isotopes in nature. One isotope has an atomic mass of 106,9 amu. The percentage appearance of this isotope is 50%. The atomic mass of the other isotope is 109,1. 4.1.1 Define the term isotope. (2) 4.1.2 Calculate the relative atomic mass of element X. (5) 4.1.3 Identify element X in QUESTION 4.1.2. (2) 4.2 Complete the table below. Write only the answer next to the question number (4.2.1–4.2.7). ELEMENT ATOMIC MASS NUMBER NUMBER NUMBER OF NUMBER NUMBER OF OF ELECTRONS PROTONS NEUTRONS Al 13 27 4.2.1 4.2.2 4.2.3 K+ 19 4.2.4 4.2.5 4.2.6 4.2.7 (7) [16] QUESTION 5 (Start on a new page.) Hydrogen peroxide decomposes at room temperature according to the following balanced chemical equation: 2H 2 O 2 (aq) → O 2 (g) + 2H 2 O(ℓ) 5.1 What does the (aq) represent in the equation above? (1) 5.2 Identify the type of reaction above. Choose between PRECIPITATION and REDOX. Give a reason for the answer. (2) 5.3 Is the reaction an example of a physical or a chemical change? (1) 5.4 Define the term one mole of a substance. (2) 5.5 If 4 moles of hydrogen peroxide decomposes, calculate the volume of gas formed at STP. (4) 5.6 Calculate the number of oxygen atoms in H 2 O 2 if 17 g of H 2 O 2 decomposes. (4) [14] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 10 DBE/November 2017 CAPS – Grade 10 QUESTION 6 (Start on a new page.) 6.1 Study the balanced chemical equation of the reaction between sodium carbonate (Na 2 CO 3 ) and hydrochloric acid (HCℓ) and answer the questions that follow. Na 2 CO 3 + 2HCℓ → 2NaCℓ + CO 2 + H 2 O Identify the type of reaction above. Choose between REDOX and GAS FORMING. (1) 6.2 In a reaction, 10,6 g of sodium carbonate reacts completely with excess hydrochloric acid. 6.2.1 Calculate the molar mass of sodium carbonate. (2) 6.2.2 Calculate the initial number of moles of sodium carbonate. (2) 6.2.3 Calculate the mass of CO 2 produced during this reaction. (4) 6.2.4 Calculate the mass of sodium chloride produced if 4,87 dm3 of carbon dioxide was produced at STP. (6) 6.3 14,2 g of a sample of hydrated sodium carbonate, Na 2 CO 3 •xH 2 O, was strongly heated until no further change in mass was recorded. On heating, all the water of crystallisation evaporated as follows: Na 2 CO 3 •xH 2 O → Na 2 CO 3 + xH 2 O Calculate the number of moles of water of crystallisation in the sodium carbonate sample, if 5,3 g of solid remained after strong heating. (5) [20] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 11 DBE/November 2017 CAPS – Grade 10 QUESTION 7 (Start on a new page.) Learners investigated the relationship between the concentration of a silver nitrate (AgNO 3 ) solution and its conductivity at a constant temperature. They set up the apparatus, as shown below, and recorded the current. The initial reading of the ammeter was taken before anhydrous AgNO 3 was added to distilled water. A The anhydrous AgNO 3 was added to 200 cm3 distilled water spoon by spoon. The ammeter reading was recorded after each spoon was added. The results are shown in the table below. SPOONS OF AgNO 3 IN AMMETER READING (mA) DISTILLED WATER 0 0 1 0,18 2 0,92 3 1,47 4 1,84 7.1 Give a reason why the ammeter reading was initially zero. (1) 7.2 Give ONE word/term for a solution that conducts electricity. (2) 7.3 Write down a balanced chemical equation to show how AgNO 3 dissociates in water. (2) 7.4 Write down the following for the investigation above: 7.4.1 A hypothesis (2) 7.4.2 Dependent variable (1) 7.4.3 Independent variable (1) 7.4.4 Controlled variable (1) 7.5 Define the term anhydrous. (1) 7.6 If the mass of AgNO 3 is 5,3 g per spoon, calculate the concentration of the solution after TWO spoons have been added. (4) Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 12 DBE/November 2017 CAPS – Grade 10 7.7 Can tap water be used for this experiment? Give a reason for the answer. (2) 7.8 From the results, deduce the relationship between the ion concentration in the solution and its conductivity. (2) 7.9 A learner accidentally dropped hydrochloric acid into the solution. 7.9.1 How will this affect the ammeter reading? Write down only INCREASE, DECREASE or REMAIN THE SAME. (1) 7.9.2 Explain the answer to QUESTION 7.9.1. (2) [22] QUESTION 8 (Start on a new page.) Your teacher asked you to use your knowledge of precipitation reactions to test the quality of water in the local river. You are provided with the following chemicals: AgNO 3 , BaCl 2 , dilute HNO 3 8.1 Which chemical would you choose to test for the presence of carbonates (CO 3 -2)? (1) 8.2 Use a balanced chemical equation to show the test for carbonates in QUESTION 8.1. (4) 8.3 Both carbonates and sulphates form a white precipitate with the chemical in QUESTION 8.1. Use a balanced chemical equation to explain how you would confirm that the precipitate is a carbonate. (4) 8.4 Give the chemical name of the precipitate formed when the carbonate and the chemical in QUESTION 8.1 reacts. (2) [11] Copyright reserved Please turn over

Downloaded from hlayiso.com Physical Sciences/P2 13 DBE/November 2017 CAPS – Grade 10 QUESTION 9 (Start on a new page.) Study the water cycle below and answer the questions that follow. A Water vapour Clouds C Oceans/ B Rivers E D Plants 9.1 The water cycle consists of many processes. Identify the following processes: 9.1.1 A (1) 9.1.2 B (1) 9.1.3 E (1) 9.2 Is energy ABSORBED or RELEASED during condensation? Give a reason for the answer. (2) 9.3 Give ONE reason why water vapour is referred to as an important greenhouse gas. (2) 9.4 The amount of rainfall in large parts of South Africa has decreased considerably recently. Various reasons have been given to explain the drought. State ONE possible strategy that a community can adopt to ensure that they have a regular supply of water. (2) [9] TOTAL: 150 Copyright reserved

Downloaded from hlayiso.com Physical Sciences/P2 1 DBE/November 2017 CAPS – Grade 10 DATA FOR PHYSICAL SCIENCES GRADE 10 PAPER 2 (CHEMISTRY) GEGEWENS VIR FISIESE WETENSKAPPE GRAAD 10 VRAESTEL 2 (CHEMIE) TABLE 1: PHYSICAL CONSTANTS/TABEL 1: FISIESE KONSTANTES NAME/NAAM SYMBOL/SIMBOOL VALUE/WAARDE 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 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 Copyright reserved

Physical Sciences/P2 Downloaded from hlayiso.com 2 DBE/November 2017 CAPS – Grade 10 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 Elektronegatiwiteit 1,9 Cu Simbool 1,0 Li 1,5 Be 2,0 B 2,5 C 3,0 N 3,5 O 4,0F Ne 63,5 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 3,0Cℓ 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 1,9Cu 1,6 Zn 1,6 Ga 1,8 Ge 2,0 As 2,4 Se 2,8Br 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 1,9Ag 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 2,5At 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