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Reaction order Half-life (days) (a) First 2 (b) First 6 (c) Second 2 (d) Zero 6 7. The number of possible enantiomeric pairs that can be produced during mono-chlorination of 2-methylbutane is (a) 3 (b) 4 (c) 1 (d) 2 8. The degree of dissociation (α) of a weak electrolyte, A x B y is related to van't Hoff factor (i) by the expression x (a) α= + y − 1 x (b) α= + y + 1 i −1 i −1 i −1 i −1 (c) α= (d) α= ( x+ y−1) x+ y+ 1 9. The coagulation values in millimoles per litre of the electrolytes used for the coagulation of As 2 S 3 are given below : I. NaCl = 52 II. BaCl 2 = 0.69 III. MgSO 4 = 0.22 The c or r e order c t of their coagulating power is (a) I > II > III (b) II > I > III (c) III > II > I (d) III > I > II 10. In the following sequence of the reactions, identify the final product D. (a) (c) (d) + (b) + 11. Pick out the incorrect statements from the following. 1. Glucose exists in two different crystalline forms, a-D-glucose and b-D-glucose. 2. a-D-glucose and b-D-glucose are anomers. 3. a-D-glucose and b-D-glucose are enantiomers. 4. Cellulose is a straight chain polysaccharide made of only b-D-glucose units. 5. Starch is a mixture of amylose and amylopectin, both contain unbranched chain of a-D-glucose units. (a) 1 and 2 only (b) 2 and 3 only (c) 3 and 4 only (d) 3 and 5 only 12. When the imidazole ring of histidine is protonated, the tendency of nitrogen to be protonated (proton migrates from –COOH) is in the order (a) b > g > a (b) g > b > a (c) g > a > b (d) b > a > g 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 : A mixture of 2-nitrophenol and 4-nitrophenol can be separated by steam distillation. Reason : 2-Nitrophenol is intramolecularly H-bonded while 4-nitrophenol is intermolecularly H-bonded. 14. Assertion : Chloroform is stored in dark coloured bottles. Reason : Chronic chloroform exposure may cause damage to liver and kidneys. 15. Assertion : Hydrometallurgy involves dissolving the ore in a suitable reagent followed by precipitation by a more electropositive metal. Reason : Copper in bulk quantity is extracted by hydrometallurgy. CHEMISTRY TODAY | APRIL ‘17 55
JEE MAIN / JEE ADVANCED / PETs Only One Option Correct Type 16. 0.001 mol of cobalt complex having molecular formula represented by Co(NH 3 ) 5 (NO 3 )(SO 4 ) was passed through a cation exchanger (RSO 3 H) and the acid coming out of it, was titrated with 0.1 M NaOH solution. For complete neutralisation of acid coming out of cation exchanger, the volume of NaOH required was 20.00 mL. From the above data we can say that the complex can be represented as (a) [Co(NH 3 ) 5 ](NO 3 )(SO 4 ) (b) [Co(NH 3 ) 5 SO 4 ]NO 3 (c) [Co(NH 3 ) 5 NO 3 ]SO 4 (d) none of the above. 17. What is the dominant intermolecular force or bond that must be overcome in converting liquid CH 3 OH to a gas? (a) Dipole-dipole interactions (b) Covalent bonds (c) London-dispersion forces (d) Hydrogen bonding 18. Calculate the amount of ice that will separate out on cooling a solution containing 50 g of ethylene glycol in 200 g of water to –9.3°C. (K f for water = 1.86 K m –1 ) (a) 161.29 g (b) 38.71 g (c) 54.12 g (d) 77.42 g 19. The incorrect statements among the following are I. NCl 5 does not exist while PCl 5 does. II. Lead prefers to form tetravalent compounds. III. The three C—O bonds are not equal in carbonate ion. IV. Both O + 2 and NO are paramagnetic. (a) I, III and IV only (b) I and IV only (c) II and III only (d) I and III only More than One Options Correct Type 20. The carbon based reduction method is not used for extraction of (a) Sn from SnO 2 (b) Fe from Fe 2 O 3 (c) Al from Al 2 O 3 (d) Mg from MgCO 3 .CaCO 3 21. For the cell, Tl|Tl + (0.001 M)||Cu 2+ (0.1 M)|Cu, E cell at 25°C is 0.826 V. The EMF can be increased (a) by increasing [Tl + ] (b) by decreasing [Tl + ] (c) by increasing [Cu 2+ ] (d) by decreasing [Cu 2+ ]. 22. Which of the following reagents can be used to oxidise primary alcohols to aldehydes? (a) CrO 3 in anhydrous medium (b) KMnO 4 in acidic medium (c) Pyridinium chlorochromate (d) Heat in the presence of Cu at 573 K 23. In a hypothetical reaction X → Y, the activation energy for the forward and the backward reactions are 15 and 9 kJ mol –1 respectively. The potential energy of X is 10 kJ mol –1 . Then (a) threshold energy of the reaction is 25 kJ (b) the potential energy of Y is 16 kJ (c) heat of reaction is 6 kJ (d) the reaction is endothermic. Integer Answer Type 24. The maximum covalency shown by Be is 25. For the Mg- Ag cell, how many times the difference between the EMF of the cell and its standard EMF will change if concentration of Mg 2+ ions is changed from 0.1 M to 0.01 M and that of Ag + ions is changed from 0.5 M to 0.25 M? SRMJEEE JEE MAIN VITEEE NATA WBJEE Kerala PET AMU (Engg.) Karnataka CET NEET MHT CET COMEDK (Engg.) BITSAT JEE Advanced J & K CET AIIMS JIPMER EXAM DATES 2017 1 st April to 30 th April (Online) 2 nd April (Offline) 8 th & 9 th April (Online) 5 th April to 16 th April (Online) 16 th April 23 rd April 24 th April (Physics & Chemistry) 25 th April (Mathematics) 30 th April 2 nd May (Biology & Mathematics) 3 rd May (Physics & Chemistry) 7 th May 11 th May 14 th May 16 th May to 30 th May (Online) 21 st May 27 th May to 28 th May 28 th May 4 th June 56 CHEMISTRY TODAY | APRIL ‘17
Page 2 and 3: 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: Class XII This specially designed c
Page 53 and 54: CHEMISTRY MUSING SOLUTION SET 44 24
Page 55 and 56: Isothermal reversible expansion :
Page 57 and 58: (a) H 2 O/H + , BH 3·THF/H 2 O 2·
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
Page 85: 90 CHEMISTRY TODAY | APRIL ‘17

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