IITJEE CHEMISTRY SAMPLE PAPER - II Data required : Atomic Mass : Na = 23, Ba = 137, C = 12, O = 16, H = 1 Atomic Number : Fe = 26, Cu = 29, Ni = 28 SECTION – I Straight Objective Type This section contains 8 multiple choice questions numbered 1 to 8. Each question has 4 choices (a), (b), (c) and (d), out of which ONLY ONE is correct. 1. Consider the following nucleophiles H2O, CH3 COO , OH, CH 3 O (I) (II) (III) (IV) The correct order of decreasing nucleophilicity of these species is (a) (I) > (II) > (III) > (IV) (b) (IV) > (II) > (III) > (I) (c) (IV) > (III) > (II) > (I) (d) (IV) > (III) > (I) > (II) 2. 3. [X] + H2SO4 [Y], a colourless gas with irritating smell [Y] + K2Cr2O7 + H2SO4 green solution. The species [X] and [Y] are (a) SO3 2 , SO2 (b) Cl , HCl (c) S–2, H2S (d) CO3 2 , CO2 X mL of 0.05 M solution of a double salt Na2CO3 · NaHCO3 · 2H2O is titrated against 0.05 M HCl. When phenolphthalein is used as indicator ‘A’ mL of HCl is required and ‘B’ mL of the same acid is required (separately) when methyl orange is the indicator. Find the ratio B/A. 1 (a) 3 (b) 3 (c) 5 (d) 2 Space for rough work 4. Assume that you are using an open-end manometer filled with mineral oil rather than mercury. What is the gas pressure in the bulb (in millimeter of Hg) if the level of mineral oil in the arm connected to the bulb is 237 mm higher than the level in the arm connected to the atmosphere and atmospheric pressure is 746 mm Hg? The density of mercury is 13.6 g/ml and the density of mineral oil is 0.822 g/ml. (a) 731.7 mm Hg (b) 983 mm Hg (c) 509 mm Hg (d) 790.3 mm Hg 5. The cubic unit cell of Al(molar mass 27 g mol–1) has an edge length of 405 pm. Its density is 2.7 g cm–3. The cubic unit cell is (a) face centered (b) body centered (c) primitive (d) hcp 6. How many isomeric bromides having molecular formula C6H13Br on conversion into Grignard reagent followed by treatment with water would yield 2, 3-dimethylbutane? (a) 1 (b) 2 (c) 3 (d) 4 7. Silver acetate + I2 In CS2 (2 : 1 Ratio) The main product of this reaction is (a) CH3I (c) CH3COI 8. In the reaction, 2CuCl2 + 2H2O + SO2 ‘A’ is (a) Cu2Cl2 (c) CuSO4 Space for rough work (b) CHI3 (d) CH3COOCH3 A + H2SO4 + 2HCl (b) Cu (d) CuS SECTION II Reasoning Type This section contains 4 reasoning type questions numbered 9 to 12. Each question contains Statement-1 and Statement-2. Each question has 4 choices (a), (b), (c) and (d), out of which ONLY ONE is correct. Directions: Read the following questions and choose (A) Statement-1 is True, Statement-2 is True ; Statement-2 is a correct explanation for Statement-1. (B) Statement-1 is True, Statement-2 is True ; Statement-2 is not a correct explanation for Statement-1. (C) Statement-1 is True, Statement-2 is False. (D) Statement-1 is False, Statement-2 is True. 9. Statement-1: Ortho-substituted anilines are normally weaker base than aniline whether the substituent is electron releasing or electron withdrawing in nature. Statement-2: Substituent at ortho position hinders the approach of H2O molecule to solvate the conjugate acid due to steric crowding. (a) A (b) B (c) C (d) D 10. Statement-1: Addition of Br2 molecule to trans-2-butene gives meso product. Statement-2: Addition of Br2 molecule to an alkene proceeds via carbocation intermediate. (a) A (b) B (c) C (d) D 11. Statement-1: The acidic character of hydrides of the group 16 elements increases in the order H2O < H2S < H2Se < H2Te Statement-2: Oxygen is more electronegative than sulphur. (a) A (b) B (c) C (d) D Space for rough work 12. Statement-1: Enthalpy changes are positive when Na2SO4. 10 H2O and salts like NaCl, KCl etc. which do not form hydrates are dissolved in water. But enthalpy changes are negative when anhydrous salts capable of forming hydrates are dissolved in water. Statement-2: The difference in the behaviour is due to large difference in the molecular weights of hydrated and anhydrous salts. The substances with larger molecular weights usually show positive enthalpy change on dissolution. (a) A (b) B (c) C (d) D SECTION III Linked Comprehension Type This section contains 2 paragraphs C13 C18. Based upon the paragraph, 3 multiple choice questions have to be answered. Each question has 4 choices (a), (b), (c) and (d), out of which ONLY ONE is correct. Passage–I The electrons in a poly-electronic atom are filled one by one in order of increasing energy level. The energy of subshells and orientation of orbitals depends upon the values of three quantum numbers (i.e., n, l and m respectively) derived from Schrodinger wave equation. However, the different orbitals of a subshell possess same energy level and are called degenerate orbitals but their energy level changes in presence of magnetic field and the orbitals are non-degenerate. A spectral line is noticed if an electron jumps from one level to other. The paramagnetic nature of element is due to the presence of unpaired electron(s). 13. Which in each pair is electronically most stable ion: Cu+ or Cu2+ and Fe2+ or Fe3+ (a) Cu+, Fe3+ (b) Cu2+, Fe3+ 2+ 2+ (c) Cu , Fe (d) Cu+, Fe2+ 14. The total magnetic moment of Ni2+ ion is (a) 6 BM (b) 8 BM (c) 15 BM (d) 12 BM Space for rough work 15. The possible number of spectral lines when an electron can jump from 5th shell to 2nd shell is (a) 4 (b) 2 (c) 3 (d) 6 Passage-II Any nucleophilic substitution reaction proceeds via two processes: (a) SN1 i.e. substitution nucleophilic unimolecular (b) SN2 i.e. substitution nucleophilic bimolecular The examples which serve for these are the solvolysis of alkyl halides. Let solvolysis of tertbutyl bromide takes place via two conditions given below. Reaction A: Here tert-butyl bromide was refluxed with ethanol containing small amount of sodium ethoxide. The reaction was proceeding with a half life of only a few minutes and this resulted in products (A) an ether and (B) C4H8. The rate for the reaction is given by the expression, Rate = k1 [tert-butyl bromide] + k2 [tert-butyl bromide] [C2H5O–] Reaction B: Here tert-butyl bromide was refluxed with a mixture of solvents containing 70% ethanol and 30% water. 16. The number of products possible for the second reaction is (a) 1 (b) 2 (c) 3 (d) reaction will not occur 17. Here the two constants k1 and k2 respectively for the reaction A are for (a) SN1 and SN2 respectively. (b) SN1 and E2 respectively. (c) E1 and SN2 respectively. (d) E1 and SN1 respectively. 18. During substitution reactions with weak base via carbocation mechanism (a) SN1 predominates (b) SN2 predominates (c) E1 predominates (d) E2 predominates Space for rough work SECTION IV Matrix Match Type This section contains 2 questions. Each question contains statements given in two columns which have to be matched. Statements (A), (B), (C), (D) in Column I have to be matched with statements (1, 2, 3, 4) in Column II. One statement in first column has one or more than one match with the statements in second column. The answers to these questions have to be appropriately bubbled as illustrated in the following example. If the correct matches are A 1,3, B 3, C 2,3 and D 2,4, then the correctly bubbled 4 × 4 matrix should be as follows: 1 2 3 4 A B C D 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1. Column I Column II (A) Variation of equilibrium constants with 1. temperature Kirchoff’s equation 2. Hess’s law 3. Van’t Hoff equation (D) Variation of heat of reaction with 4. temperature –57.2 kJ/equivalent (B) Hneutralisation of H–Cl. (C) Law of conservation of energy. 2. Column I Column II (A) Cellulose 1. Anomers (B) 2. Epimers -D glucose and -D-glucose (C) Glucose and Mannose 3. Polymer (D) Protein 4. can be hydrolysed Space for rough work SECTION V Subjective or Numerical Type The answer to these questions would lie between 0 to 9999. For any answer all four bubbles must be filled, for example if you plan to answer as 16 then fill 0016 and if you plan to answer 0 then fill 0000 in the grid provided in answer sheet. In case the answer is a fraction, round it off to the nearest whole number. For example, 725.3 is rounded off to 0725. Any incomplete filling will be considered as incorrect filling. Illustration: If you want to fill 2379 as your answer then it will be filled as 1. How many mole of electrons are required to reduce 1.5 mole of nitro-benzene into aniline, if current efficiency, in this experiment is 50%. 2. What is the pH of a mixture obtained by mixing 75 ml M/5 HCl and 25 ml M/5 NaOH aqueous solution? Space for rough work