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Class XI This specially designed column enables students to self analyse their extent of understanding of complete syllabus. Give yourself four marks for correct answer and deduct one mark for wrong answer. Self check table given at the end will help you to check your readiness. Total Marks : 120 NEET / AIIMS Only One Option Correct Type 1. At the same temperature calculate the ratio of average velocity of SO 2 to CH 4 . (a) 2 : 3 (b) 3 : 4 (c) 1 : 2 (d) 1 : 6 2. In which of the following the oxidation number of oxygen has been arranged in increasing order? (a) OF 2 < KO 2 < BaO 2 < O 3 (b) BaO 2 < KO 2 < O 3 < OF 2 (c) BaO 2 < O 3 < OF 2 < KO 2 (d) OF 2 < O 3 < KO 2 < BaO 2 3. For an indicator, HIn as the pH changes from pK In – 1 to pK In + 1, [ B ] (a) will vary from 0.1 to 10 [ A] (b) will vary from 10 to 0.1 (c) will vary from 1 to 10 (d) will vary from 10 to 1. 4. If 30 mL of H 2 and 20 mL of O 2 react to form water, what is left at the end of the reaction? (a) 10 mL of H 2 (b) 5 mL of H 2 (c) 10 mL of O 2 (d) 5 mL of O 2 5. The enthalpy of hydrogenation of cyclohexene is –119.5 kJ mol –1 . If resonance energy of benzene is –150.4 kJ mol –1 , its enthalpy of hydrogenation would be (a) –269.9 kJ mol –1 (b) –358.5 kJ mol –1 (c) –508.9 kJ mol –1 (d) –208.1 kJ mol –1 6. Borate salts when heated with conc. H 2 SO 4 and C 2 H 5 OH produce characteristic green colouration on flame due to the formation of a volatile compound (a) (C 2 H 5 ) 3 B (b) B 2 H 6 (c) (C 2 H 5 ) 3 BO 3 (d) B 2 O 3 7. In diborane (B 2 H 6 ) there are (a) three 3c-2e – bonds and three 2c-2e – bonds (b) four 3c-2e – bonds and two 2c-2e – bonds (c) two 3c-2e – bonds and four 2c-2e – bonds (d) none of the above. 8. Cl 2 and SO 2 are pollutants but used in bleaching of textiles. Bleaching action of Cl 2 and SO 2 is due to Cl 2 SO 2 (a) oxidation oxidation (b) reduction reduction (c) reduction oxidation (d) oxidation reduction 9. The correct IUPAC name of is (a) 2-carboxypropane-1, 3-dioic acid (b) 2-carboxymalonic acid (c) 1, 1,1-tricarboxymethane (d) propane-1, 2, 3-tricarboxylic acid. 10. (CH 3 ) 2 CHCH CH 2 changes to A, B and C by using (CH 32 )CHCH2CHOH, 2 (CH 32 )CHCHCH 3 , ( ) Time Taken : 60 Min. OH ( B) CHEMISTRY TODAY | APRIL ‘17 61
(a) H 2 O/H + , BH 3·THF/H 2 O 2·NaOH, Hg(OAc) 2 /NaBH 4·NaOH (b) H 2 O/H + , Hg(OAc) 2 /NaBH 4·NaOH, BH 3·THF/H 2 O 2·NaOH (c) BH 3·THF/H 2 O 2·NaOH, Hg(OAc) 2 / NaBH 4·NaOH, H 2 O/H + (d) BH 3·THF/H 2 O 2·NaOH, H 2 O/H + , Hg(OAc) 2 /NaBH 4·NaOH 11. The number of electrons involved in the reduction of nitrate ion to hydrazine is (a) 8 (b) 7 (c) 5 (d) 3 12. A certain mass of gas occupies a volume of 300 cc at 27°C and 620 mm pressure. The volume of this gas at 47°C and 640 mm pressure will be (a) 400 cc (b) 510 cc (c) 312 cc (d) 350 cc Assertion & Reason Type Directions : In the following questions, a statement of assertion is followed by a statement of reason. Mark the correct choice as : (a) If both assertion and reason are true and reason is the correct explanation of assertion. (b) If both assertion and reason are true but reason is not the correct explanation of assertion. (c) If assertion is true but reason is false. (d) If both assertion and reason are false. 13. Assertion : It is impossible to determine the exact position and exact momentum of an electron simultaneously. Reason : The path of an electron in an atom is clearly defined. 14. Assertion : Kjeldahl method is not applicable to nitro compound, azo compound and pyridine. Reason : Kjeldahl method is used for halogen estimation. 15. Assertion : Bromobenzene upon reaction with Br 2 /Fe gives 1, 4-dibromobenzene as the major product. Reason : In bromobenzene, the inductive effect of the bromo group is more dominant than the mesomeric effect in directing the incoming electrophile. JEE MAIN / JEE ADVANCED / PETs Only One Option Correct Type 16. An inorganic compound (X) which produces brick red colouration as flame. When (X) dissolves in water produces alkaline solution and a combustible gas (Y).(X) and (Y) are respectively. (a) CaO, O 2 (b) Ca 3 N 2 , NH 3 (c) CaCO 3 , CO 2 (d) CaH 2 , H 2 17. The correct order of acidic strength is (a) Cl 2 O 7 > SO 2 > P 4 O 10 (b) K 2 O > CaO > MgO (c) CO 2 > N 2 O 5 > SO 3 (d) Na 2 O > MgO > Al 2 O 3 18. The degree of dissociation of dinitrogen tetraoxide, N 2 O 4(g) 2NO 2(g) at temperature T and total pressure P is α. Which one of the following is the correct expression for the equilibrium constant (K p ) at this temperature? 2 2α α P (a) (b) 2 ( 1 − α) ( 1 − α) 2 4α 2 4α P (c) 2 (d) ( 1 − α ) 2 ( 1 − α ) 19. The configuration of 2, 3-dichloropentane whose structure is shown, is (a) 2R, 3R (c) 2S, 3R (b) 2R, 3S (d) 2S, 3S More than One Options Correct Type 20. Which of the following are wrong statements? (a) NO is more harmful than NO 2 . (b) SO 2 is more harmful than SO 3 . (c) Acid rain contains mainly HNO 3 . (d) Acid rain contains mainly H 2 SO 4 and lesser concentrations of HNO 3 and HCl. 21. 22.44 kJ energy is required to convert 8 g of gaseous atom of metal M to M + (g) if I.E. 1 of metal M = 374 kJ/mol. Select correct statement for metal M. (a) 0.6 mole gaseous ion (M + ) are formed. (b) Same energy can convert all M + (g) to M 2+ (g) . (c) Atomic mass of metal = 133.33 g mol –1 . (d) 3.613 × 10 22 atoms of M are converted to M + (g). 62 CHEMISTRY TODAY | APRIL ‘17
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Volume 26 No. 4 April 2017 Managing
Page 5 and 6: (R) K[Co(NH ) (NO ) 4 ] 1. The volu
Page 7 and 8: 24. m-Bromoaniline can be prepared
Page 9 and 10: (a) (b) (c) (d) CH CH C CH CH CH C
Page 11 and 12: 20. (d) : CH 2 5 alk. KMnO 4 ( A) C
Page 13 and 14: 41. (a) : According to Gibbs’-Hel
Page 15 and 16: 5. Compound 'X' C 7 H 8 O, is insol
Page 17 and 18: (c) (d) O HC 2 O O HC 2 O O CH CH C
Page 19 and 20: 4. As 2 S 3 sol carries a negative
Page 21 and 22: 15. Cl CHONa + EtOH 2 5 Heat Possib
Page 23 and 24: (c) If θ = 10°, the charge underg
Page 25 and 26: (c) (d) NH 2 O heat NH HO 2 C CO 2
Page 27 and 28: (c) Dil. HCl followed by reaction w
Page 29 and 30: 33. Which of the following reaction
Page 31 and 32: Balz-Schiemann reaction : tetrauoro
Page 33 and 34: 26. (c) : HC 3 HC 3 -H O CH 2 3 H +
Page 35 and 36: 12. At equimolar concentration of F
Page 37 and 38: (a) 1s 2 , 2s 2 2p 6 , 3s 2 3p 6 3d
Page 39 and 40: Fraction of M present as M 2+ = 88
Page 41: 26. (b) : According to Gay-Lussac
Page 47 and 48: CONCEPT MAP PERIODICITY IN PROPERTI
Page 49 and 50: Class XII This specially designed c
Page 51 and 52: JEE MAIN / JEE ADVANCED / PETs Only
Page 53 and 54: CHEMISTRY MUSING SOLUTION SET 44 24
Page 55: Isothermal reversible expansion :
Page 59 and 60: 22. H 2 can be obtained from 28. Th
Page 61 and 62: 7. Predict the product for the foll
Page 63 and 64: 7. (d) : Cyclopropane is under seve
Page 65 and 66: 46. If the first and the (2n - 1) t
Page 67 and 68: 1 (a) 6 2 ms − (b) 4 2 (c) 7 m s
Page 69 and 70: tension, viscous force, weight but
Page 71 and 72: (a) HN 2 SO 3 H (b) (NH 2 ) 2 CO (c
Page 73 and 74: SOLUTIONS PAPER-I 1. (a) : The phot
Page 75 and 76: 11. (a, d) : As, F 1 = k 1 x, F 2 =
Page 77 and 78: Given that, at equilibrium, ⎛ n
Page 79 and 80: 2 ∫ 53. (3) : (| x− 2| + [ x])
Page 81 and 82: percentage change in v = 1 2 perce
Page 83 and 84: Again, c 2 a 2 b 2 = + + 2a⋅b
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