Arrange the following alkene in increasing order of their enthalpy of hydrogenation ( )

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1 Q.1. Which of the statements is correct? (I) Melting point of alkane increases with increase of C atoms and with increase in branching. (II) Boiling point of alkane increases with increase of C atoms but with decrease in branching. (III) Cycloalkanes have lower boiling point than normal alkane with same number of C atoms. (IV) Alkenes have lower boiling point than same number of C atoms in alkanes. (I), (II) (I), (II),(III) (III), (IV) (IV) Correct Answer 1 Conceptual Q.2. Assertion : Among isomeric alkanes, branching increase the boiling points. Reason : Branching lowers the intermolecular van der Waal s force of attraction. Both assertion and reason are true and reason is the correct explanation for Both assertion and reason are true but reason is not the correct explanation for Assertion is true and reason is false Assertion is false and reason is true. Correct Answer 4 Branching decreases the boiling points. Q.3. Arrange the following alkene in increasing order of their enthalpy of hydrogenation - H ( ) III < IV < II < I III < IV < I < II I < II < III < IV I < II < IV < III Correct Answer 1 More the hyperconjuction structure less would be their hydrogenation enthalpy. Q.4. Which of the following would not form upon electrolysis of aqueous solution of potassium propanoate? Butane Ethyl ethanoate Ethyl propanoate Ethene Correct Answer 2

2 Won t give Q.5. Correct Answer Is Integer Type How many monochlorinated products can be obtained from all the isomeric alkanes having the formula C 5 H 10 (excluding stereoisomers)? Total 6. Passage Text Q.6. Compound (A) is: 2, 3-Dimethylbutane 2-Methylpentane 2, 2-Dimethylbutane 3-Methylpentane Correct Answer 2

3 Q.7. Compound (B) is: 2, 3-Dimethylbutane 2-Methylpentane 2, 2-Dimethylbutane 3-Methylpentane Correct Answer 1 Q.8. Two isomeric hexyl chlorides obtained from (B) are : Correct Answer 4 Q.9. The alkenes (C) and (D) are:

4 Correct Answer 1 Q.10. Which of the following is incorrect regarding combustion of alkanes? It is always an exothermic process It proceeds through a free radical mechanism It can be controlled to an intermediate stage 2-methyl butane will liberate less heat than n-pentane. Correct Answer 4 Conceptual Q.11. The bond dissociation energy of the C - H bond for the compound H 3 C - H H 3 C - CH 2 - H (P) (Q) Decreases in the order: P > Q > R > S S > R > Q > P S > P > Q > R Q > P > S > R Correct Answer 3 More the bond dissociation energy more unstable it will become after dissociations. Q.13. Choose the correct comparisons: For B.pt use dipole moment more dipole more B.pt. (M.pt) generally terms have greater M.pt.

5 Q.14. The boiling point of trans-dichloroethene is 48 degree Celsius. Which number best approximates the boiling point of cis-dichloroethene? 36 degree Celsius 42 degree Celsius 48 degree Celsius 54 degree Celsius Correct Answer 4 54 degree Celsius Q.15. Choose the major product of reaction I II III IV Correct Answer 3 Q.16. What is the major product when 2, 2-dimethyl-cylohexanil is heated in acid? 3, 3-dimethylcyclohexene 2, 3-dimethylcyclohexene 2, 2-dimethylcyclohexene 1, 2-dimethylcyclohexene Correct Answer 4

6 Q.17. P should be None of these Correct Answer 1 Q.18. Among these alcohols, which of the following orders is correct about their ease of dehydration under acidic condition? I>ΙΙ>III III>ΙΙ>I II >Ι >III III>Ι>II Correct Answer 2 ( 3> 2>1easeof dehydration ) Q.19. Among these alcohols, which of the following orders is correct about their ease of

7 dehydration under acidic condition? I>ΙΙ>III III>ΙΙ>I II >ΙII >I II>Ι>III Correct Answer 2 III>ΙΙ>I Q.23. Assertion : Alkenes usually undergo electrophilic addition reaction at carbon-carbon double bond. Reason : Electrophilic addition at double bond produces carbocation intermediate. If both assertion and reason are correct and reason is the correct explanation of If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false. If reason is true but assertion is false. Correct Answer 2 The carbocation is stable Electrophilic Q.24. Assertion : A mixture of alkene and alkane can be separated by passing the mixture through a cold, concentrated sulphuric acid solution. Reason : Alkene is absorbed in the solution while alkane passes unreacted. If both assertion and reason are correct and reason is the correct explanation of If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false. If reason is true but assertion is false. Correct Answer 1 Conceptual. Q.26. Arrange the following alkene in increasing order of their enthalpy of hydrogenation - H ( ) R < S < Q < P R < S < P < Q P < Q < R < S P < Q < S < R Correct Answer 1 More the hyperconjuction structure less would be their hydrogenation enthalpy.

8 Q.27. Assertion : Hydrogenation of an alkene is always an exothermic process. Reason : Alkane has lower potential energy than an alkene. If both assertion and reason are correct and reason is the correct explanation of If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false. If reason is true but assertion is false. Correct Answer 1 Q.28. Assertion : Addition of HBr in presence of a peroxide (ROOR) to propene gives 2-bromo propane. Reason : Reaction involves a bromine free radical. If both assertion and reason are correct and reason is the correct explanation of If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false. If reason is true but assertion is false. Correct Answer 4 Q.29. H 2 C = CH 2 CH 3 - CH = CH 2 Which of the following alkenes is most reactive towards electrophilic addition reaction? H 2 C = CH - Cl Correct Answer 3 More Hyper conjugations structure Carbocation is stabilized. Q.30.

9 Both (1) and (2) in same amount None of the above Correct Answer 2 Q.31. Which of the following reactions are correctly represented? H R - CH = CH + HI 2 O 2 R-CH - CH -I 2 hv 2 2 H R - CH = CH + HBr 2 O 2 R -CH - CH -Br 2 hv 2 2 Q.32. Assertion : Addition of HCI to 3-methyl - 1- butane gives 20 chloro-2-methyl butane as the major product. Reason : Rearrangement of carbocation to more stable carbocation leads to formation of major product. If both assertion and reason are correct and reason is the correct explanation of If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false. If reason is true but assertion is false. Correct Answer 1 Q.33. Which molecule will give following dicarboxylic acid upon treatment with acidic solution of KMnO 4?

10 Correct Answer 4 Q.34. Assertion : Treatment of one mole of 2-butene with O 3 followed by workup with H 2 O 2 gives 2 mole of acetic acid. Reason : H 2 O 2 bring about oxidative cleavage of intermediate ozonide. If both assertion and reason are correct and reason is the correct explanation of If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false. If reason is true but assertion is false. Correct Answer 1

11 Q.35. An organic compound or reaction with O 3 followed by Zn and H 2 O gives Q.36. A triene treated with ozone followed by CH 3 - S - CH 3 to give following three products. What is the structure of triene?

12 Correct Answer 3 Q.37. What is the final product of the following rection? Correct Answer 3 Q.38. Which of the following compounds produces - 1, 5-cyclooctanedione on ozonolysis?

13 Correct Answer 2 Q.39. Q.40. Examine the structural formulas of following compounds and find how many compounds will produce CO 2 on oxidative ozonolysis. Correct Answer 0005 Is Integer Type

14 Q.41. An unknown alkene (A) reacts with 3 mole of H 2 gas in presence of platinum catalyst to from 1- isopropyl 4-methyl cyclohexane. When unknown alkene (A) is ozonized and reduced, following product are obtained Correct Answer 2 Q.42. Which of the statements are correct for alkyne with molecule formula C 6 H 10? It shows 7 structural isomers. It shows 4 terminal and 3 internal alkynes. It shows 3 terminal and 4 internal alkynes

15 Only one isomer is chiral. Q.43. What is the relationship between the two terminal H 2 C = groups in a cumulene containing three consecutive double bonds (H 2 C = C = C = CH 2 )? They are in the perpendicular plane They are in the same plane They are in two planes at They are in two planes at Option 5 They are in two planes at Correct Answer 2 Even Allenes are in same plane. Q.44. What is the major product in the reaction? Correct Answer 4 Q.46. What will be formed in the following Kolbe s electrolysis? 2 - butane 1 - butyne 2 - butyne

16 Both b and c Correct Answer 3 Q.47. Which of the following will produce a visible change with 1- butyne and can be used to differentiate it from 2- butyne? Ag(NH 3 ) 2 + Cu(NH 3 ) 2 + KMnO 4 /H + Br 2 They react only with terminal triple bond. Q.50. Which of the following will react will 1- butyne? AgNO 3 + NH 4 OH Cu 2 Cl 2 + NH 4 OH Na - KMnO /OH 4 AgNO 3 + NH 4 OH and Cu2 Cl 2 + NH 4 OH will give Na will form salt KMnO /OH will oxidize CO 4 2 Q.52. H C C 1.NaNH2 H CH A 2 B: 3 2.CH3CH2Br Pd BaSO4 A ish3c CH 2 C CH A is CH 3 C C CH2CH3

17 Q.53. Assertion: 2- butyne on controlled hydrogenation with pd/caco 3 in presence of PbO gives cis-2-butene. Reason : Hydrogenation occur at the surface of metal containing adsorbed hydrogen. If both assertion and reason are correct and reason is the correct explanation of If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false. If reason is true but assertion is false. Correct Answer 2 Conceptual Q.54. Assertion : Propyne is more reactive than propene towards electrophilic addition of HBr. Reason : Propyne has greater electron density available for electrophile due to two pibonds therefore more electrophile If both assertion and reason are correct and reason is the correct explanation of If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false. If reason is true but assertion is false. Correct Answer 4 Vinyllic carbocation is less stable than 2 0 carbocation. Q.55. Assertion : Ozonolysis of 3-hexane followed by hydrolysis gives propanoic acid. Reason : The byproduct H 2 O 2 oxidizes ozonide to acid. If both assertion and reason are correct and reason is the correct explanation of If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false. If reason is true but assertion is false. Correct Answer 1

18 Q.56. P should be CH 3 CH 2 CHO + CH 3 CHO CH 3 CH 2 COOH + CH 3 COOH None of these Correct Answer 2 Q.57. Which of the following cannot be used to prepare Cumene from benzene? CH 3 CH = CH 2, HF CH 3 CH 2 CH 2 Cl, AlCl 3 CH 3 CH 2 CH 2 OH, BF 3 Correct Answer 3 b, c - Rearrangement Q.58. Which will undergo friedal Craft alkylation reaction? 1 and 3 2 and 4 1 and 2 1, 2 and 4 Correct Answer 2 2 and 4 are electro- donating group ( activations) Q.60. Based on the above reaction, P should be

19 Mixture of (a) and (b) None of these Correct Answer 2 HO - Cl + electrophile is Cl + Q.61. Which of the following cations are more stable than benzyl cation?

20 Because : NH 2, CH 3, OCH 3 stabilize carbocation Q.62. Issopropyl benzene can be obtained by : Passage Text We need CH CH CH A benzene ring deactivated by strong and moderate electron withdrawing group that is, any meta directing group, is not electron rich enough to undergo Friedel Crafts reactions. Friedel Crafts reaction also do not occur with NH 2 group as it react AlCl 3 and Produc deactivating group. Q.62. Which of the following compounds undergo Friedel Crafts alkylation reaction?

21 Correct Answer 3 Q.63. Which of the following cannot be starting material for this compound Correct Answer 3 Other can be starting material. Q.64. Which of the following sequence of reaction is correct for the synthesis of product

22 All are incorrect Correct Answer 3 Q.65. Examine the structural formulas shown below and find out how many compounds can not, give Friedel Craft reaction.

23 Correct Answer 0006 Is Integer Type Do not give friedel craft. Q.66.

24 Correct Answer 3 Q.67. The predominant product is Correct Answer 2 Para to CH 3 (donating group).

25 Q.68. The final predominant product is Correct Answer 2 Q.69. In which of the following the incorrect place for electrophilic substitution has been indicated?

26 Correct Answer 3 Q.70. CH 3 CH 2 X,AlCl 3 Which of the following is not the appropriate way of conversion? Br, Fe; C 2 H 5 MgCl, ether Br 2, Fe; CH 3 Br; Na, ether Correct Answer 3 Q.71. Product of monochlorination of the compound

27 Correct Answer 2 NH ii donating pare to NH Q.73. Rank in order of increasing rate of reaction towards EAS with bromine in the presence of FeBr 3 B < A < C B < C < A A < B < C A < C < B Correct Answer 1

28 Would be least because of EWG in C has very less effect on ring. B < A < C Q.76. Assertion : Toluene undergoes nitration much more readily than benzene. Reason : It is due to electron releasing nature of CH3 group which increases electron density on benzene and electrophilic substitution reaction like nitration becomes faster. If both assertion and reason are correct and reason is the correct explanation of If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false. If reason is true but assertion is false. Correct Answer 1 Conceptual Passage Text Aromatic compounds can easily show electrophilic substitution reaction due to the presence of pie electron clouds above and below the plane of aromatic ring. This ring can be easily attached by electrophiles due to high electro density. The mechanism of these reaction is common in general which can be given as follows: Q.77. In which of the following compounds the rate of electrophilic substitution (Halogenation) is fastest? Correct Answer 4

29 Q.78. Which of the following resonance structures is not a contributor to the cyclo hexa dienyl cation intermediate in the halogenation of benzene? Correct Answer 3 Conceptual Q.79. Which of the following σ - complexes generated by the attack of an electrophile of benzene ring has lowest energy?

30 Correct Answer 4 Is most stable lowest energy Q.80. Mark the following in increasing order of stability for different Gs for the following Wheland complex. 1) CH 3 2) NO 2 3) OCH 3 4) Correct Answer 2143 Is Integer Type (Order of stabilizing power) Q.81. For the following reaction of substituted benzene, mark the answer using the following guide line i) If substitution takes place at ortho/para position mark 1. ii) If substitution takes place at meta, mark 2. iii) If reaction takes place at position other than these, mark 3. iv) In case of no reaction, mark 4. A) G = CH 3. Reaction with CH 3 Cl,AlCl 3 B) G = CH 3. Reaction with Cl 2,hv. C) G = NO. Reaction with Cl 2,Fe. D) G = NO 2. Reaction with CH 3 Cl,AlCl 3 Correct Answer 1324 Is Integer Type

31 Q.82. An electrophile, E + attacks the benzene ring to generate the intermediate σ-complex. Of the following, which σ-complex is of lowest energy? Correct Answer 2 Is most stable lowest energy.

32 Q.83. The sulfonic acid group is often readily replaced by a nitro group e.g. This is beacause -SO 3 H group is a better leaving group than NO 2 group in electrophilic substitution -NO 2 group is a better leaving group than SO 3 H group in electrophilic substitutions This is a nucleophilic substitution. Both b and c Correct Answer 1 Conceptual Q.84. In which of the followings, reactant and product are correctly matched?

33 Q.85. No reaction Correct Answer 2 Is not correct because of steric factor between CHO and -Br Q.87. Which of the following are deactivating but ortho, para directing during electrophilic aromatic substitution reaction?

34 Passage Text Q.91. Conceptual If aromatic ring is substituted by more than groups then electrophilic aromatic substitution reaction take place according to more activating group. Types of group which donate electron in aromatic ring known as activating groups. Find out correct product of reaction.

35 No reaction Correct Answer 1 Since para w.r.t is already occupied it will occupy ortho position. Q.92. Major product formation take place at which position in this reaction? Correct Answer 2 Para of most activating group. Q.93. Find out major product of following reaction:

36 Correct Answer 3 Para of NH Q.94. Identify number of substituents those are deactivating but ortho and para directing Correct Answer 0005 Is Integer Type Aare deactivating but ortho para directing. Q.95. Each of the compounds shown below has two aromatic ring, labled as A and Identify number of compounds in which ring B is more active than ring A for electrophilic aromatic substitution reaction.

37 Correct Answer 0005 Is Integer Type Q.96. Examine the structural formulas shown below and find out how many compounds undergo electrophilic nitration more rapidly tha.

38 Correct Answer 0006 Is Integer Type Are better than flouro benzene Q.97. Assertion : Benzene does not decolourise alkaline KmnO 4. Reason : Benzene is stabilized by resonance and π electrons are delocalized. If both assertion and reason are correct and reason is the correct explanation of assertion If both assertion and reason are true but reason is not the correct explanation of If assertion is true but reason is false If reason is true but assertion is false. Correct Answer 1 Conceptual Q.98. In this reaction which ring will be reduced, by hydrogenation. Correct Answer 0002 Is Integer Type 1, 3, 4 are supporting 2. Q.99. Examine the structural formulas shown below and find out how many compounds will show oxidation reaction with acidic KMnO 4

39 Correct Answer 0004 Is Integer Type Will oxidize. Q.100. The main product is Correct Answer 2

I. Multiple Choice Questions (Type-I)

Unit 13 HYDROCARBONS I. Multiple Choice Questions (Type-I) 1. Arrange the following in decreasing order of their boiling points. (A) n butane (B) 2 methylbutane (C) n-pentane (D) 2,2 dimethylpropane A