Chemistry-5.Work Book (Phase- V)

Work Book (Phase  V) Subjective: Board Type Questions 1. Assign d, and meso character to the following (i) (ii) (iii) (iv) 2. Write structure of (2Z, 4E)  3  ethyl  2, 4  hexadiene. 3. Biological reduction of pyruvic acid gives (+) lactic acid, represented by Fischer projection shown. Assign R/S configuration. 4. Assign R and S configuration to the products when cyclopentene reacts with (a) cold KMnO4 (b) Br2 water 5. Identify the product of the following reaction with proper configuration. 6. In the following molecules indicate presence of a centre of chirality with an asterisk (*). (a) (b) 7. Are the following compounds chiral – enatiomers or achiral-Identical mirror images? 8. Give the aldol condensation product of CH3CH = CHCHO. 9. Arrange the following in increasing extent of hydration. 10. Explain the reason for the stability of choral hydrate. 11. What is the product of the following reaction? 12. In which of the following compounds would you except intramolecular H bonding to occur (a) o – nitro phenol (b) o – hydroxybenzoic acid (c) o – fluoro phenol (d) methyl salicylate (oil of winter green) 13. Outline steps of the following conversion 14. Convert (a) acetylene into n-butyl alcohol. (b) propane into 1 – propanol, 2 – propanol and allyl alcohol. 15. An organic compound with molecular formula C10H18O contains no double or triple bonds. It reacts with hydrochloric acid to give dichloride as shown Deduce the structure of the organic compound. 16. Would it be possible to form di-t-butyl ether from dehydration of t-butyl alcohol? 17. Suggest reaction conditions for the following conversion 18. Predict the most acidic hydrogen in the following compounds. (a) (b) (c) (d) 19. Which of the following compounds would be expected to decarboxylate when heated? (a) (b) (c) (d) 20. Saponification of esters of optically active alcohols proceeds with retention of configuration. Explain. 21. Calculate volume of N2¬ gas obtained at NTP from 1mL of body fluid containing 6 g of urea. 22. Barbituric acid is formed when diethyl malonate reacts with urea. What is the type of isomerism shown by it? 23. Convert CH3COOH into (CH3)2NH. 24. Arrange the following in increasing basic nature. True and False 25. Tertiary alcohols are more reactive towards halogen acids than secondary alcohols. 26. 2-Pentanol or 3- pentanol on treatment with HCl gives both 2-chloropentane and 3-chloropentane. 27. Terminal Gem-dihalides on hydrolysis yield aldehydes. 28. m-Chlorobromobenzene is an isomer of m-bromochlorobenzene. 29. Aldehydes react with alcohols in presence of dry HCl gas to form acetals. 30. Aldehyde group is m-directing and deactivates the benzene ring towards further electrophilic substitution reactions. 31. Bromination of propionic acid with bromine in presence of small amount of red phosphorus gives acid. 32. Acid chlorides react with aromatic hydrocarbons in presence of anhydrous AlCl3 to form aromatic ketones. Fill in the Blanks 33. A mixture of phenol and phthalic anhydride when heated with conc. H2SO4 forms…………..which is used as an ……in acid-base titrations. 34. Phenol on treatment with bromine water gives……..but with bromine in CS2, it mainly gives………. 35. Chloropicrin is formed by the action of ……on chloroform. 36. Alkyl halide with……….Ag2O gives alcohol and ………………Ag2O gives ether. 37. The reaction of acetyl chloride with diethylcadmium followed by hydrolysis gives……….. 38. The structure of the intermediate product formed by the oxidation of toluene with CrO3 and acetic anhydride, whose hydrolysis gives benzaldehyde, is………… 39. Oxidation of o-xylene with alkaline KMnO4 gives………… 40. Hell-Volhard-Zelinsky reaction involves the replacement of an ……….atom from the alkyl group of a monocarboxylic acid by a ……atom. IIT Level Question 41. Comment on the chirality of the following molecules (a) (b) 42. For each of the following additions, predict the regiochemistry of each adduct and determine whether the product mixture is optically active. If not, determine whether the inactivity results from the absence of chiral centres, the formation of equal amounts of enantiomers or formation of a meso compound. (a) (b) 43. Comment upon the nature of products in the following. (a) (b) 44. Identify A to E in the following 45. Identify products in the following reaction (a) (b) (c) 46. Identify A, B and C. Identify A, B and C. 47. What is wrong in these reactions? (a) (b) 48. Identify the products (a) (b) 49. Explain the difference in the following observation 50. The pKa values for the amino acid cysteine are 1.8, 8.3 and 10.8. Assign these pKa values to the functional groups in cysteine and draw the structure of the molecule in aq. Solution at pH 1, 5, 9. Objective: Multiple choice questions with single correct options 1. Configuration at C1 and C2 atoms are: (A) (B) (C) R and R (D) R and S 2. A and B are (A) achiral identical mirror images (B) chiral enantiomers (C) geometrical isomers (each separately) (D) racemic mixture 3. Which of the following compounds are enantiomers? (A) (B) (C) (D) 4. Meso – tartaric acid is optically inactive due to the presence of (A) two chiral carbon atoms (B) molecular unsymmetry (C) molecular symmetry (D) external compensation 5. Which of the following compounds can occur in enantiomeric forms? (A) (B) (C) (D) 6. Ethylene glycol reacts with excess of PCl5 to give (A) 1, 1 – dichloroethane (B) 1, 2 – dichloroethane (C) 1, 1, 1 – trichloroethane (D) 2, 2 – dichloroethane 7. How many structures of F are possible? (A) 2 (B) 5 (C) 6 (D) 3 8. The product A will be (A) (B) (C) (D) 9. The final product is (A) (B) (C) (D) None of the above 10. During dehydration of alcohols to alkanes by heating with conc. H2SO4, the initial step is (A) formation of an ester (B) protonation of alcohol molecule (C) formation of carbocation (D) elimination of water 11. The correct acidic order of the following is (A) I > II > III (B) III > I > II (C) II > III > I (D) I > III > II 12. What is formed when glycerol reacts with HIO4? (A) 2 formic acid molecules and one formaldehyde molecule (B) 2 formaldehyde and one formic acid molecule (C) 3 formic acid molecules (D) 3 formaldehyde molecules 13. Phenol is heated with phthalic anhydride in presence of conc. H2SO4. The product gives pink colour with alkali. The product is (A) phenolphthalein (B) bakelite (C) salicylic acid (D) fluorescein 14. The reaction of with RMgX leads to the formation of (A) RCHOHR (B) RCHOHCH3 (C) R2CHCH2OH (D) RCH2CH2OH 15. In the following compounds The order of acidity is (A) III > IV > I > II (B) I > IV > III > II (C) II > I > III > IV (D) IV > III > I > II 16. An organic compound ‘X’ on treatment with acidified K2Cr2O7 gives a compound ‘Y’ which reacts with I2 and sodium carbonate to form triiodomethane. The compound ‘X’ is (A) CH3OH (B) CH3COCH3 (C) CH3CHO (D) CH3CHOHCH3 17. In the reaction of phenol with CHCl3 and aqueous NaOH at 70C (343K ), the electrophile attacking the ring is (A) CHCl3 (B) •CHCl2 (C) :CCl2 (D) COCl2 18. The compound which gives most stable carbonium ion on dehydration is (A) (B) (C) (D) 19. An ether is more volatile than alcohol having the same molecular formula. This is due to (A) intermolecular hydrogen bonding in alcohols (B) dipolar character of ether (C) alcohols having resonance structure (D) intermolecular hydrogen bonding in ethers 20. X could be (A) LiAlH4 (B) NaBH4 (C) LiAlH4/BF3 (D) NaH 21. A is (A) (B) (C) (D) 22. P is (A) (B) (C) (D) 23. A compound X of molecular formula C4H10O is soluble in conc. H2SO4. It does not react with sodium metal but is cleaved by HI to give CH3I and an alcohol Y which gives iodoform. ‘X’ may be (A) C2H5OC2H5 (B) CH3OCH2CH2CH3 (C) C2H5CHOHCH3 (D) 24. A is (A) (B) (C) (D) 25. Which one is not cyclic ether? (A) (B) (C) (D) 26. A is (A) (B) (C) (D) 27. (A) (B) (C) (D) None 28. A and B are (A) (B) (C) (D) 29. (A) (B) (C) (D) 30. What are A, B and C in the following? (A) (b) (C) (D) 31. A is (A) (B) (C) (D) 32. m-chlorobenzaldehyde on reaction with conc. KOH at room temperature gives (A) potassium m-chlorobenzoate and m-hydroxy benzaldehyde (B) m-hydroxybenzaldehyde and m-chlorobenzyl alcohol (C) m-chlorobenzyl alcohol and m-hydroxybenzyl alcohol (D) potassium m-chlorobenzoate and m-chlorobenzyl alcohol 33. The end product ‘C’ in the following sequence of chemical reactions is (A) acetaldehyde oxime (B) formaldehyde oxime (C) methyl nitrate (D) acetoxime 34. In cannizzaro reaction given below: the slowest step is (A) the attack of OH at the carbonyl group (B) transfer of hydride ion to carbonyl group (C) abstraction of proton form carboxylic acid (D) deprotonation of Ph  CH¬2OH 35. Reduction with aluminium isopropoxide in excess of isopropyl alcohol is called MPV reduction. What will be the final product when cyclohex-2-enone is selectively reduced by MPV reduction? (A) cyclohexanol (B) cyclohex-2-enol (C) cyclohexanone (D) benzene 36. Which of the following reagents convert C6H5COCHO to C6H5CHOHCOOH? (A) aq. NaOH (B) Acidic Na¬2SO3 (C) Na2CrO4/H2SO4 (D) NaNO2/HCl 37. The enol form of acetone, after treatment with D2O, gives (A) (B) (C) (D) 38. Reduction of can be carried out with (A) catalytic reduction (B) Na/C2H5OH (C) Wolff-Kishner reduction (D) LiAlH4 39. Identify the compounds A and B in the following reaction sequence (A) (B) (C) (D) 40. Which of the following has the most acidic hydrogen? (A) 3-hexanone (B) 2, 4 – hexanedione (C) 2, 5 – hexanedione (D) 2, 3 – hexanedione 41. A mixture of benzaldehyde and formaldehyde on heating with aq. NaOH solution gives (A) benzyl alcohol and sodium formate (B) sodium benzoate and methyl alcohol (C) sodium benzoate and sodium formate (D) benzyl alcohol and methyl alcohol 42. Major product is (A) (B) (C) (D) 43. Compound ‘A’ (molecular formula C3H8O is treated with acidified potassium dichromate to form a product ‘B’ (molecular formula C3H6O). ‘B’ forms a shining silver mirror on warming with ammonical silver nitrate. ‘B’ when treated with an aq. solution of NH2CONHNH2.HCl and sodium acetate gives a product ‘C’. Identify the structure of ‘C’. (A) (B) (C) (D) 44. Which of the following compounds would have the smallest value for pKa? (A) CHF2CH2CH2COOH (B) CH3CH2CF2COOH (C) CH2FCHFCH2COOH (D) CH3CF2CH2COOH 45. When CH2 = CH  COOH is reduced with LiAlH4, the compound obtained will be (A) (B) (C) (D) 46. Identify the correct order of boiling points of the following compounds:- (A) I > II > III (B) III > I > II (C) I > III > II (D) III > II > I 47. The major product obtained when Br2 / Fe is treated with (A) (B) (C) (D) 48. An ester (A) with molecular formula C9H10O2 was treated with excess of CH3MgBr and the complex so formed was treated with H2SO4 to give an olefin (B). Ozonolysis of (B) gave a ketone with molecular formula C8H8O which shows positive iodoform test. The structure of (A) is: (A) C6H5COOC2H5 (B) CH3COCH2COC6H5 (C) p – CH3O – C6H4 – COCH3 (D) C6H5COOC6H5 49. (A) (B) (C) (D) 50. X and Y in the following reaction sequence are:- (A) R – CN, RCH2NH2 (B) RNH2, RCN (C) RCN, RNH2 (D) RCN, RCH2NH2 Multiple choice questions with more than one option correct 51. 1 – propanol and 2 – propanol can be best distinguished by (A) oxidation with KMnO4 followed by reaction with Fehling solution (B) oxidation with acidic dichromate followed by reaction with Fehling solution (C) oxidation by heating with copper followed by reaction with Fehling solution (D) oxidation with KMnO4 followed by reaction with Tollen’s solution 52. Which of the following statements are correct? (A) CrO3.H2SO4 in acetone oxidizes 2° alcohols to ketones (B) Jones reagent which is chromic acid in aqueous acetone solution oxidizes 1° alcohol to aldehyde and 2° alcohol to ketone but does not effect double bond. (C) chromic acid oxidizes 1° alcohols to carboxylic acid. (D) the formation of cyanohydrin from a ketone is an example of electrophilic addition 53. Product is (A) (B) (C) (D) 54. How much bromine is needed to produce tribromophenol from one mole of phenol? (A) 3.0 mole (B) 1.5 mol (C) 240 g (D) 480 g 55. Which of the product expected in the following reaction? (A) (B) (C) (D) None of these 56. Which of the following reactions depict the nuclophilic substitution of C2H5Br? (A) (B) (C) (D) 57. Which of the following are electrophilic substitution reactions? (A) (B) (C) (D) None of these 58. On treatment with a clear solution of CrO¬3 in dilute H2SO4, an aliphatic alcohol gives a greenish opaque solution within 2-3 seconds. The alcohol can be (A) CH3CH2OH (B) (C) (D) 59. Treatment of n-propylamine with nitrous acid gives (A) CH3CH=CH2 (B) CH3¾CH2¾CH2OH (C) (D) none of these 60. Which of the following statements are correct? (A) The two carbon-oxygen bond length in formic acid are different. (B) The two carbon-oxygen bond lengths in sodium formate are equal (C) The carbon-oxygen bond length in formic acid is less than that in sodium formate. (D) The carbon-oxygen bond length in formic acid is greater than that in sodium formate 61. Nitration of phenol with dilute nitric acid at 293 K gives (A) o-nitrophenol (B) p-nitrophenol (C) m-nitrophenol (D) 2, 4, 6-nitrophenol 62. The product obtained in the equation: is (A) ClCH2NO¬2 (B) Cl2CHNO2 (C) Cl3CNO2 (D) CH3NH2 63. Phenyl cyanide can be obtained by (A) (B) (C) (D) 64. Isopropylamine can be obtained by (A) (B) (C) (D) none of these 65. Which of the following will yield p-tert. Butylphenol? (A) (B) (C) (D) None of these 66. Which of the following statements are correct? (A) Benzaldehyde reduces Fehling’s solution (B) is a Claisen-Schmidt reaction. (C) pKa (formic acid) is less than pKa (acetic acid) (D) o-Toluidine is more basic than aniline 67. Which of the following statements are correct? (A) When phenol vapour is passed over Zn dust, bezene is produced. (B) The phenolic OH group is ortho and para directing (C) o-nitrophenol has a lower boiling point than p-nitrophenol (D) Phenol is more acidic than o-cresol 68. Which of the following will give vinyl chloride? (A) (B) (C) (D) 69. Vinyl chloride undergoes (A) addition reactions (B) elimination reactions (C) substitution reactions (D) none of these 70. Which of the following methods can be used for the preparation of acetylene? (A) (B) (C) (D) None of these 71. Aryl halides undergo (A) the Fittig reaction (B) the Ullmann reaction (C) the Grignard reaction (D) none of these 72. Which of the following reagents can be used to distinguish CH2=CHCH2Cl from CH3CH2CH2Cl? (A) Na fusion; HNO3, AgNO3 (B) Ag(NH3)2OH (C) AgNO3/C2H5OH (D) Br2/CCl4 73. Alkyl iodides can be prepared by (A) (B) (C) (D) 74. The reaction of glycerol with HIO4 gives (A) formaldehyde (B) formic acid (C) iodic acid (D) oxalic acid 75. On being treated with HCl, acetone gives (A) mesityl oxide (B) phorone (C) mesitylene (D) aldol Match the Following 76. Match the following: X Y Z 1. Decarboxylation 1. LiAlH4 1. a-bromoacids 2. Hell-Volhard Zelinsky reaction 2. Aq. sodium ethanoate 2. Carboxylic acids 3. Grignard reagents 3. Sodalime 3. Ethane 4. Electrolysis 4. Br2 in presence of red P 4. Alcohols 5. Reduction of aldehydes and ketones with 5. Dry ice (solid CO2) 5. Removal of CO2 77. Match the statements given in Column A with Column B. Column A Column B 1. Methanal disproportionates in the presence of conc. Alkali (a) Benzoin condensation 2. (b) Acetaldehyde 3. Aldehyde which gives iodoform test (c) Wolf-Kishner reduction 4. (d) Cannizzaro’s reaction 78. Match the following Column A and Column B Column A Column B 1. Williamson’s synthesis (a) Estimation of alkoxy groups 2. Zeisel method (b) Reaction of phenol with diethyl sulphate in presence of NaOH 3. Oxonium salts (c) Involves heating of an alkyl halide with sodium alkoxide 4. Phenetole (d) Combination of ethers with inorganic acid 79. Match the following Column A and Column B Column A Column B 1. Tollen’s reagent (a) 50% NaOH solution 2. CH3COCH3 (b) Hexamethylenetetramine 3. HCHO (c) Oxidising agent 4. HCHO + NH3 (d) Ba(OH)2 Comprehension 1 In a polyhydric alcohol, the total numbers of hydroxyl groups are estimated by the following methods: (i) A known mass of the acetyl derivative of polyhydric alcohol is taken. It is mixed with an excess volume of a standard alkali solution. Both are refluxed. Alkali is used in the hydrolysis of acetyl derivative. The unused alkali is measured by doing titration with a standard acid solution and total number of hydroxyl groups (n) can thus be calculated stoichiometrically. (ii) Total number of –OH groups in vicinal position can be calculated by periodic acid or lead tetra acetate oxidation. Read the above paragraph carefully and give the answer of following questions: 80. 0.436 g of acetyl derivative of a polyhydric alcohol (molecular mass = 92) require 0.336 g KOH for hydrolysis. The total numbers of hydroxyl group(s) in the alcohol are: (A) 1 (B) 2 (C) 3 (D) 4 81. The product formed by reaction of ethylene glycol and periodic acid (HIO4) is: (A) Acetic acid (B) Formic acid (C) Formaldehyde (D) Glyoxal 82. A compound with molecular formula C4H10O3 is converted by the action of acetyl chloride to a compound with molecular weight 190. The original compound has: (A) One –OH group (B) Two –OH groups (C) Three –OH groups (D) No –OH group 83. The ratio of the number of moles of lead tetra acetate required for the oxidation of 1 mole of glucose to that of 1 mole of fructose is: (A) 1 : 1 (B) 2 :1 (C) 5 : 4 (D) 4 : 5 Comprehension  2 Aldehyde & Ketone are polar molecule. Nucleophiles attacks >C = O at carbon (positively charged) and electrophiles are attacked by oxygen. The characteristic reaction of Aldehyde & Ketone is nucleophilic addition to the carbon of carbonyl group. In condensation of Aldehyde & Ketone takes place only when it consist carbon atom consisting , the reaction will takes place in presence of dilute alkali in this one Aldehyde is partially converted to its enolate anion by base. The enolate undergoes nucleophilic addition to the carbonyl group. The alkoxide formed in nucleophilic addition step then abstracts a proton from the solven to yield aldol consisting aldehydes & hydroxyl group. The reactivity of carbonyl compound for nucleophilic addition depends on inversely of +I effect. Read the above paragraph carefully and answer the questions given below it: 84. Which of the following undergoes aldol condensation? (A) (B) (C) (D) 85. (A) (CH3)2 – NH (B) (CH3)3 – N (C) (CH3)3C – NH2 (D) None 86. Which one is most reactive for addition of alcohol on carbonyl group? (A) C6H5CHO (B) HCHO (C) (D) CH3.CHO 87. How many aldol products can form when 2 butanone & propanal reacts in presence of dilute base: (A) 4 (B) 5 (C) 6 (D) 7 Comprehension  3 To convert 1-bromopropane into 1-bromobutane, chemists A and B designed two paths. Chemist A: Chemist B: Based on these methods, answer the following questions: 88. Better yield of CH3CH2CH2CH2Br is obtained by (A) chemist A (B) chemist B (C) equally in both (D) no prediction can be made 89. While attempting synthesis, assistant of B read the instruction as Then product formed would have been (A) CH3CH2CH2CH2OH (B) CH3CH2CH¬2OH (C) CH3CH2CH3 (D) all of these 90. Chemist A had the problem of getting so many side products in step I beside getting n-butane. These side products are (A) (B) (C) (D) 91. Chemist A obtained a resolvable optically inactive mixture in step II, as major product. This mixture contains: (A) 1-bromobutane and 2-bromobutane (B) d-and -2-bromopropane (C) d-and -3-bromopentane (D) d-and -2-bromobutane Comprehension  4 Alkyl halides undergo SN reactions as well as E1, E2 and ECB reactions, depending on the nature of substrate and nucleophile. Carboxylic acids can be converted into -bromo carboxylic acids and thus it can be used as intermediate in the synthesis of so many other compounds. Based on the above intermediate, answer the following questions: 92. A used to carry out this conversion is (A) PBr3 (B) PBr5 (C) P; Br2/H2O (D) Br2,  93. One sub-intermediate is also formed in the above reaction: (A) (B) (C) (D) No sub intermediate is formed 94. Conversion of a carboxylic acid into -halo carboxylic acid is called (A) Cannizzaro reaction (B) Refromatsky reaction (C) Perkin reaction (D) Hell-Volhard-Zelinsky reaction 95. For the above conversion reagent used is (A) alcoholic NaOH (B) NaOH, H+ (C) both of these (D) none of these ANSWERS TO GRAND ASSIGNMENT Subjective: Board Type Questions 1. (i) and (iii) meso (ii) d – isomer (iv) 2. 3. (S) 4. (a) (b) 5. 7. Chiral – enantiomers 8. In this case condensation of allylic hydrogen and not that of vinylic hydrogen takes place. 11. 13. 15. 21. 22. Tautomerism 24. III < I < II True and False 25. T 26. T 27. T 28. F 29. T 30. T 31. F 32. T Fill In the Blanks 33. phenolphthalein, indicator 34. 2, 4, 6-tribromophenol, 4-bromophenol 35. nitric acid 36. moist, dry 37. butanone 38. C6H5CH(OCOCH3)2 39. phthalic acid 40. alpha hydrogen, halogen IIT level Questions 41. (a) There is no chiral carbon, but the molecule is chiral (an allene) (b) There is no chiral carbon and there is a plane of symmetry between two ¾CH3 groups. Hence it is not a chiral molecule. 42. (a) (b) 43. (a) There is no change in configuration (stereospecific retention) (b) A mixture is formed due to SN1 reaction (racemisation) 44. E : H2/Pd/BaSO4 or sulphur in quinoline. 45. 46. 47. (a) In basic medium Nu- attacks oxiranes at the less substituted carbon. (b) Carbocation undergoes rearrangement 48. 50. Objective: 1. C 2. A 3. A 4. C 5. B 6. B 7. D 8. A 9. A 10. B 11. B 12. B 13. A 14. D 15. D 16. D 17. C 18. B 19. A 20. C 21. C 22. C 23. D 24. A 25. D 26. B 27. A 28. B 29. B 30. D 31. B 32. D 33. D 34. B 35. B 36. A 37. B 38. C 39. B 40. B 41. A 42. B 43. A 44. B 45. C 46. B 47. A 48. A 49. B 50. C 51. C, D 52. A, B, C 53. A, D 54. A, D 55. A,B 56. A, C, D 57. A, B 58. A, B, C 59. A, B, C 60. A, B, C 61. A, B 62. A, B, C 63. A, B, D 64. A, B, C 65. A, B, C 66. C, D 67. A, B, C, D 68. A,B,C, D 69. A, B 70. A, B, C 71. A, B, C 72. C, D 73. B, C 74. A, B, C 75. A, B 76. 1–3–5, 2–4–1, 3–5–2, 4–2–3, 5–1–4 77. 1–d, 2–a, 3–b, 4–c 78. 1–c, 2–a, 3–d, 4 –b 79. 1–c, 2–d, 3–a, 4–b 80. C 81. C 82. B 83. A 84. A 85. C 86. A 87. C 88. B 89. C 90. C 91. D 92. C 93. B 94. D 95. B