ICSE Class X Chemistry Practice Questions PDF

PREFACE With a growing emphasis on competency-based education globally, the educational landscape in India has also steered towards high-quality learning experiences that allow learners to incorporate critical thinking and problem-solving approaches. This approach goes beyond rote memorisation and f...

PREFACE With a growing emphasis on competency-based education globally, the educational landscape in India has also steered towards high-quality learning experiences that allow learners to incorporate critical thinking and problem-solving approaches. This approach goes beyond rote memorisation and focuses on developing the skills and knowledge that students need to apply in their real-world scenarios. The Council for the Indian School Certificate Examinations (CISCE), as a national-level progressive examination board, has taken several steps to infuse competency-based education in CISCE schools through teacher capacity-building on item development for competency-based assessments and the incorporation of competency-focused questions at the ICSE and ISC levels from the examination year 2024. To further facilitate the adoption of competency-based assessment practices in schools and to support teachers and students towards the preparation for attempting higher-order thinking questions in future board examinations, Item Banks of Competency-Focused Practice Questions for selected subjects at the ICSE and ISC levels have been developed. This Item Bank consists of a rich variety of questions, both objective and subjective in categories, aimed at enhancing the subject-specific critical and analytical thinking skills of the students. In this Item Bank, each question is accompanied by the topic and cognitive learning domain/s that it intends to capture. The cognitive domains reflected in these questions include understanding, analysis, application, evaluation and creativity, along with some questions of the higher-order recall domain. The Answer Key at the end presents the possible answers to a given question, but it is neither limiting nor exhaustive. These practice questions are also meant to serve as teacher resources for classroom assignments and as samplers to develop their own repository of competency-focused questions. Apart from offering a good practice of higher-order thinking skills, engaging with these questions would allow students to gauge their own subject competencies and use these assessments for learning to develop individual learning pathways. During the development of this Item Bank, a large pool of questions was prepared by a team of experienced CISCE teachers. The questions that were finalised by the internal and external reviewers as being higher-order competency-focused questions have been collated in this item bank. I acknowledge and appreciate all the ICSE and the ISC subject matter experts who have contributed to the development and review of these high-quality competency-focused questions for CISCE students. We are hopeful that teachers and students will utilise these questions to support their teaching-learning processes. July 2024 Dr. Joseph Emmanuel Chief Executive & Secretary CISCE  PREFACE With a growing emphasis on competency-based education globally, the educational landscape in India has also steered towards high-quality learning experiences that allow learners to incorporate critical thinking and problem-solving approaches. This approach goes beyond rote memorisation and focuses on developing the skills and knowledge that students need to apply in their real-world scenarios. The Council for the Indian School Certificate Examinations (CISCE), as a national-level progressive examination board, has taken several steps to infuse competency-based education in CISCE schools through teacher capacity-building on item development for competency- based assessments and the incorporation of competency-focused questions at the ICSE and ISC levels from the examination year 2024. To further facilitate the adoption of competency-based assessment practices in schools and to support teachers and students towards the preparation for attempting higher-order thinking questions in future board examinations, Item Banks of Competency-Focused Practice Questions for selected subjects at the ICSE and ISC levels have been developed. This Item Bank consists of a rich variety of questions, both objective and subjective in categories, aimed at enhancing the subject-specific critical and analytical thinking skills of the students. In this Item Bank, each question is accompanied by the topic and cognitive learning domain/s that it intends to capture. The cognitive domains reflected in these questions include understanding, analysis, application, evaluation and creativity, along with some questions of the higher-order recall domain. The Answer Key at the end presents the possible answers to a given question, but it is neither limiting nor exhaustive. These practice questions are also meant to serve as teacher resources for classroom assignments and as samplers to develop their own repository of competency-focused questions. Apart from offering a good practice of higher-order thinking skills, engaging with these questions would allow students to gauge their own subject competencies and use these assessments for learning to develop individual learning pathways. During the development of this Item Bank, a large pool of questions was prepared by a team of experienced CISCE teachers. The questions that were finalised by the internal and external reviewers as being higher-order competency-focused questions have been collated in this item bank. I acknowledge and appreciate all the ICSE and the ISC subject matter experts who have contributed to the development and review of these high-quality competency-focused questions for CISCE students. We are hopeful that teachers and students will utilise these questions to support their teaching- learning processes. July 2024 Dr. Joseph Emmanuel Chief Executive & Secretary CISCE Chemistry ICSE – Class X Table of Contents Type of Questions Pg. No I. Multiple-Choice Questions 2 II. Fill in the Blanks 16 III. Match the Following 18 IV. One Word Answer 22 V. Structural Diagram 23 VI. IUPAC Names 25 VII. Very Short Answer Questions 27 VIII. Short Answer Questions 28 IX. Long Answer Questions 32 Answer Key 37 ICSE Competency-Focused Practice Questions 1 Chemistry ICSE – Class X COMPETENCY-FOCUSED PRACTICE QUESTIONS ICSE - CLASS X Chemistry I: Multiple Choice Questions (1 Mark Each) S.No. Questions 1. [Analytical Chemistry] Ravi was asked to identify the cation present in the salt solution. He added one of the reagents given below and got a reddish-brown precipitate. The reagent that he used is: (a) Silver nitrate solution (b) Barium chloride solution (c) Ammonium hydroxide (d) Calcium chloride solution [Understanding] 2. [Study of Compounds] Which metal does not react with HCl to form a colourless, odourless gas which burns with a pop sound? (a) Ca (b) Mg (c) Cu (d) Zn [Recall & Understanding] 3. [Study of Compounds] Prateek added warm water to magnesium nitride, and a colourless gas evolved, which, when tested with phenolphthalein, turned it pink. The gas evolved is: (a) Carbon dioxide (b) Ammonia (c) Nitrogen (d) Hydrogen chloride [Understanding] ICSE Competency-Focused Practice Questions 2 Chemistry ICSE – Class X S.No. Questions 4. [Organic Chemistry] Which of the following statements about ethane is false? (a) It is a saturated hydrocarbon. (b) It undergoes a substitution reaction. (c) It is a gas at ordinary temperatures. (d) It has a triple bond between the carbon atoms. [Recall & Understanding] 5. [Metallurgy] Thermite mixture is used to weld the broken ends of the iron girders. This mixture consists of ferric oxide and aluminium powder, which, when heated, produces molten iron. In this reaction, the aluminium powder acts as a/an _________ agent. (a) oxidising (b) reducing (c) dehydrating (d) corroding [Application] 6. [Electrolysis] The above diagram represents the electrolysis of acidulated water. The reaction occurring at the anode is: (a) H2SO4 → 2H+ + SO42- (b) H2O → H+ + OH- (c) H+ + e- → H, 2[H] +2[H] → H2 (d) OH- - e- → OH, [4OH] → 2H2O + O2 [Recall & Understanding] ICSE Competency-Focused Practice Questions 3 Chemistry ICSE – Class X S.No. Questions 7. [Period Properties and Variations of Properties] Group Numbers IA IIA IIIA IVA VA VIA VIIA VIIIA 1 2 13 14 15 16 17 18 Li D O J Ne A Mg E Si H K B C F G L With reference to the portion of the periodic table given above, identify the element having the largest atomic size: (a) Li (b) B (c) K (d) L [Understanding] 8. [Electrolysis] The picture given below shows an apparatus that a teacher used for demonstrating the properties of ionic substances. The teacher heats a sample of lead bromide in a crucible which contains two electrodes which are part of the circuit shown. The bulb does not light up. What is the best explanation for this? (a) The circuit is complete. (b) Molten lead bromide does not conduct electricity. (c) The sample of lead bromide was not heated up to the melting point by the teacher. (d) The DC power supply was set up correctly. [Analysis] ICSE Competency-Focused Practice Questions 4 Chemistry ICSE – Class X S.No. Questions 9. [Period Properties and Variations of Properties] Element Y is in Group IIA of the Periodic Table. Y reacts with element Q to form an ionic compound. Which equation shows the process that takes place when Y forms ions? (a) Y + 2e- → Y2+ (b) Y – 2e -→ Y2- (c) Y + 2e- → Y2– (d) Y – 2e- → Y2+ [Understanding & Application] 10 [Electrolysis] The diagram below shows a circuit used to electrolyse aqueous sodium argento cyanide. Which arrow indicates the movement of the silver ions in the electrolyte and of the electrons in the external circuit? Silver ions Electrons (a) 3 1 (b) 3 2 (c) 2 4 (d) 4 1 [Understanding & Application] 11. [Mole Concept and Stoichiometry] The relative atomic mass of nitrogen is 14, and that of hydrogen is 1. This means that (i)_______ of nitrogen has the same mass as (ii)________ of hydrogen. (i) (ii) (a) An atom 28 molecules (b) An atom 7 molecules (c) A molecule 14 atoms (d) A molecule 7 atoms Which words correctly complete the gaps? [Analysis] ICSE Competency-Focused Practice Questions 5 Chemistry ICSE – Class X S.No. Questions 12. [Study of Compounds] A student reacts copper turnings with cold dilute nitric acid in a test tube. He tests the gas given off with moist red and blue litmus paper. What is the name of the gas that evolved and what is the final colour of the litmus paper? Gas Final colour of the litmus paper (a) NO No change in blue and red litmus paper (b) NO2 Blue litmus turns red and no change in red litmus (c) N2 No change in blue and red litmus paper (d) N2O No change in blue and red litmus paper [Understanding] 13. [Chemical Bonding] Which element forms a stable ion with the same electronic configuration as argon? (a) Magnesium (b) Fluorine (c) Chlorine (d) Sodium [Recall & Understanding] 14. [Organic Chemistry] The diagram below represents the molecule of an organic compound. What is the name of this compound? (a) Pentanol (b) Butanol (c) Butanoic acid (d) Pentanoic acid [Understanding] ICSE Competency-Focused Practice Questions 6 Chemistry ICSE – Class X S.No. Questions 15. [Electrolysis] When a compound was electrolysed using inert electrodes, the gas released at the anode made a glowing splinter rekindle. The electrolyte that will not produce such gas observation at the anode is: (a) diluted solution of NaCl. (b) concentrated solution of NaCl. (c) diluted solution of copper sulphate. (d) acidified water. [Application] 16. [Organic Chemistry] Which of the following chains of hydrocarbons undergoes two steps of reactions to become saturated? | | (a) – C – C – | | | | (b) – C = C – | | (c) C≡C \/ C (d) / \ –C–C– / \ [Understanding & Analysis] ICSE Competency-Focused Practice Questions 7 Chemistry ICSE – Class X S.No. Questions 17. [Study of Compounds] Given below are four different illustrations of preparing hydrochloric acid drawn by students. Which of these is the correct? [Evaluate] 18. [Organic Chemistry] When two organic compounds A and B react together in the presence of conc.H2SO4, a fruity smell evolved from one of the products. If A has the functional group [-O-H], which of the following stands for the functional group of B? H | (a) – C = O | (b) – C = O || (c) – C – OH (d) – O – [Application & Analysis] ICSE Competency-Focused Practice Questions 8 Chemistry ICSE – Class X S.No. Questions 19. [Chemical Bonding] Given below are four covalent compounds. (A) H2O (B) CCl4 (C) Cl2 (D) NH3 Which of the following represents the correct order when they are arranged in their increasing number of covalent bonds? (a) B < D F - >Mg2+ > Na+ (Ionic radii) 32. (c) I, II and III 33. (c) P-Fe, Q-Zn, R-Ag 34. (a) X= CuO, Y=black, Z = reducing property 35. A is true, but R is not the correct explanation of A. 36. (a) Both A and R are correct. 37. (c) A is correct but R is not the correct explanation of A. 38. (a) A is true, and R is the correct explanation of A. 39. (i) hydroxyl (ii) deep blue (iii) reducing agent (iv) ammonium chloride 40. Reducing agent 41. X=Y ICSE Competency-Focused Practice Questions 38 Chemistry ICSE – Class X S.No. Expected Answers 42. C5H8 and C4H10 43. 3 44. Oxidised, loss 45. Addition, unsaturated hydrocarbon 46. Right 47. Higher 48. (d) HCl < HNO3< CH3COOH 49. (a) Cu 50. (a) iv (b) v (c) i) (d) ii (e) iii 51. (a) iii (b) i (c) ii (d) v (e) iv 52. (a) ii (b) v (c) i (d) iii (e) iv 53. (a) iii (b) ii (c) v (d) i (e) iv 54. (a) iv (b) v (c) i (d) ii (e) iii 55. (a) iv (b) v (c) ii (d) i (e) iii 56. (a) ii (b) i (c) iv (d) v (e) iii 57. (a) v (b) iv (c) i (d) vi (e) iii 58. (a) v (b) iv (c) i (d) ii (e) iii 59. Ammonium / NH4 + 60. 10 61. 6 62. X/4 63. XCl 64. Hydrogen sulphide gas ICSE Competency-Focused Practice Questions 39 Chemistry ICSE – Class X S.No. Expected Answers 65. -CH3 (methyl) 66. Molar volume 67. Sodium nitrate / Potassium nitrate 68. Mineral 69. H H | | H-C-C-H | | Cl Cl 70. H O | || H- C- C - OH | H 71. 72. H | H – C = CH – CH – CH3 | CH3 73. ICSE Competency-Focused Practice Questions 40 Chemistry ICSE – Class X S.No. Expected Answers 74. 75. 76. Or 77. 2-methyl -1-butene 78. 3-bromobutanoic acid 79. 2-methyl propan-2-ol 80. 2-methyl propanol 81. Butanoic acid 82. 3-methyl hexane 83. Propanal 84. Carbon dioxide gas forms a white ppt with calcium hydroxide, while with sodium hydroxide, it does not. 85. Hydrogen chloride is highly soluble even in the minute traces of moisture present in the air. 86. The bond between aluminum and oxygen is very strong / aluminum oxide is very stable. It cannot be reduced by common reducing agents like carbon, carbon monoxide or hydrogen. ICSE Competency-Focused Practice Questions 41 Chemistry ICSE – Class X S.No. Expected Answers 87. Pure acetic acid, on cooling below 16.5°C, crystallises out to form a crystalline mass re- sembling ice. 88. No, because the melting point of copper is very high. 89. A coloured dye is added to ethyl alcohol to denature it so as to prevent the misuse (consumption) of alcohol. 90. Element C will top the group because ionisation energy decreases down the group. 91. (c) silver nitrate and zinc chloride Silver chloride is formed, which is an insoluble precipitate, while for all others, no precipitate is formed 92. (a) OH ions/ hydroxyl ions (b) To prevent back suction of water or to increase area of absorption 93. As the forward reaction is exothermic (1) increasing the temperature will make the reaction to reverse and thereby decrease (1) the yield of ammonia. 94. Chloromethane / methyl chloride 95. (a) C4H8 + 6O2→ 4CO2 + 4H2O (b) 96. A white ppt. is formed H2SO4 +BaCl2 → BaSO4 + 2HCl 97. (a) 4NH3 + 5O2 → 4NO+ 6H2O (b) The platinum continues to glow even after heating is discontinued because the reaction is exothermic. 98. (a) C12H22O11+conc. H2SO4 12C+11H2O (b) Conc. H2SO4 is a dehydrating agent ICSE Competency-Focused Practice Questions 42 Chemistry ICSE – Class X S.No. Expected Answers 99. (a) If Ferrous sulphate is left exposed to air for some time, then it will be oxidised to ferric sulphate and it will not respond to the test. (b) Nitroso ferrous sulphate. 100. (a) KClO3 = 122.5 KCl = 74.5 245g of KClO3 liberates 67.2 l of O2 367.5g of KClO3 gives 67.2 x 367.5/245= 100.8 l of O2 (b) 2x122.5g of KClO3 forms 74.5g of KCl 367.5g of KClO3 forms 74.5 x 367.5/245=111.75g of KCl 101. Duralumin is light and strong, while aluminium is light and weak. It is also unaffected by moist air. It is corrosion-resistant and has high tensile strength. 102. (a) Krish’s container is heavier (b) Both the containers have the same number of atoms. 103. (a) B (b) C 104. (a) Ions (b) Metal P 105. (a) Step 2: Froth floatation instead of leaching (b) Step 3: Roasting instead of calcination 106. (a) Nickel 107. Propanol Structure ICSE Competency-Focused Practice Questions 43 Chemistry ICSE – Class X S.No. Expected Answers 108. (a) Prevents burning of carbon anodes in air or prevents heat loss by radiation. (b) Carbon anodes are oxidized and hence consumed (c) Lowers the fusion point of the mixture or enhances the conductivity of the mixture or enhances the mobility of the mixture. 109. (a) NH3 + 3PbO → 3Pb + 2H2O + 2NO2 (b) Zn + 4HNO3 → Zn (NO3)2 + 2H2O + 2NO2 (c) 2H2SO4 + S → 3SO2 + 2H2O 110. (a) Zn +2HCl → ZnCl2 + 2HCl (b) ZnCl2 + 2NaOH → Zn (OH)2 + 2NaOH (c) Zn (OH)2 + H2SO4 → ZnSO4 + 2H2O 111. (a) Cathode (b) Ni+2 + 2e → Ni (c) Block of nickel 112. (a) 1000c.c of the gas weighs 30g So 22400c.c of the gas weighs 30 x22400/1000 = 672g Molecular weight of the gas = 672g (1) V.D of the gas = 672/2 = 336 (1) (b) 22.4litres of the gas contains 6.023x10²³ molecules So, 44.8 litres of the gas contain 6.023x10²³x2 molecules = 12.046 x 10²³ molecules (1) 113. (a) X2O3 + 6HCl → 2XCl3 + 3H2O (b) 3 (c) Oxidation 114. (a) NaOH (b) C2H5OH (c) NaOH + H2SO4 → Na2SO4 + H2O (d) Sodium plumbite 115. (a) As the number of shells are less the attraction by the nucleus on the electrons is more so more energy is required to remove the electron from the outermost shell (b) Fourth period 116. (a) Barium sulphite (b) BaSO3 + 2HCl → BaCl2 + H2O + SO2 (c) Sulphur dioxide ICSE Competency-Focused Practice Questions 44 Chemistry ICSE – Class X S.No. Expected Answers 117. (a) C4H6 or (c) CnH2n-2 118. (a) Electroplating (b) Iron (c) To prevent from rusting. 119. (a) Calcium Carbide (b) (ethyne/acetylene) (c) CaC2 + 2H2O → Ca(OH)2+ C2H2 120. (a) c) 8 (b) Alkaline earth metals 121. (a) NH3 ICSE Competency-Focused Practice Questions 45 Chemistry ICSE – Class X ICSE Competency-Focused Practice Questions 46