Assignment on ALDEHYDES & KETONES with answers., Assignments of Organic Chemistry

Download Assignment on ALDEHYDES & KETONES with answers. and more Assignments Organic Chemistry in PDF only on Docsity! 1278 Aldehydes and Ketones Introduction 1. Reaction of acetaldehyde with HCN followed by hydrolysis gives a compound which shows[MP PET 1997] (a) Optical isomerism (b) Geometrical isomerism (c) Metamerism (d) Tautomerism 2. In aldehydes and ketones, carbon of carbonyl group is [MP PMT 1995; RPET 1999, 2000] (a) 3sp hybridised (b) 2sp hybridised (c) sp hybridised (d) Unhybridised 3. The IUPAC name of the following structure is OCH OHCHCHCCHCH 3 ||| 223  [MP PMT 1995] (a) 1-hydroxy 4-methyl 3-pentanone (b) 2-methyl 5-hydroxy 3-pentanone (c) 4-methyl 3-oxo 1-pentanol (d) Hexanol-1, one-3 4. Glyoxal is [BVP 2003] (a) OCHOCH 22  (b) OHCH OHCH 2 | 2 (c) CHO CHO | (d) CHO OHCH | 2 5. Aldehydes are isomeric with (a) Ketones (b) Ethers (c) Alcohols (d) Fatty acids 6. Which of the following compounds does not contain an OH group [CPMT 1982] (a) Phenol (b) Carboxylic acid (c) Aldehydes (d) Alcohols 7. IUPAC name of 33COCHCH is [MP PET 1991] (a) Acetone (b) 2-propanone (c) Dimethyl ketone (d) Propanal 8. What is the compound called if remaining two valencies of a carbonyl group are satisfied by two alkyl groups [CPMT 1990] (a) Aldehyde (b) Ketone (c) Acid (d) Acid chloride 9. CN OH H CCH | | 3  is (a) Acetaldehyde cyanohydrin (b) Acetone cyanohydrin (c) Cyanoethanol (d) Ethanol nitrile 10. Ethanedial has which functional group(s) (a) One ketonic (b) Two aldehydic (c) One double bond (d) Two double bond 11. In the group OC R R   the carbonyl carbon is joined to other atoms by (a) Two sigma and one pi bonds (b) Three sigma and one pi bonds (c) One sigma and two pi bonds (d) Two sigma and two pi bonds 12. Which of the following types of isomerism is shown by pentanone [MP PMT 1995] (a) Chain isomerism (b) Position isomerism (c) Functional isomerism (d) All of these 13. IUPAC name of CHOCCl3 is [MP PMT/PET 1988] (a) Chloral (b) Trichloro acetaldehyde (c) 1, 1, 1-trichloroethanal (d)2, 2, 2-trichloroethanal 14. Which of the following is a mixed ketone[AFMC 1997] (a) Pentanone (b) Acetophenone (c) Benzophenone (d) Butanone 15. Chloral is [CPMT 1976, 84] (a) CHOCCl3 (b) 33COCHCCl (c) 33COCClCCl (d) OHCHCCl 23 16. Carbonyl compounds are usually (a) Ethers, aldehydes, ketones and carboxylic acids (b) Aldehydes, ketones and carboxylic acids (c) Aldehydes and ketones (d) Carboxylic acids 17. Acetone and acetaldehyde are [KCET 1998] (a) Position isomers (b) Functional isomers (c) Not isomers (d) Chain isomers 18. Which of the aldehyde is most reactive ?[DCE 2004] (a) CHOHC 56 (b) CHOCH3 (c) HCHO (d) All the equally reactive Preparation 1. The end product in the following sequence of reaction is    ][ %20 1%HgSO 3 42 4 OMgXCH SOH BACHHC [Bihar CEE 2002] (a) Acetic acid (b) Isopropyl alcohol (c) Acetone (d) Ethanol 2. In the following reaction, product P is Cl O CR ||  P BaSOPd H 4 2   [CBSE PMT 1991, 2000, 02; Kerala CET 2001; Aldehydes and Ketones 1279 IIT 1992; AIIMS 1997; AFMC 1998] (a) OHRCH 2 (b) COOHR (c) RCHO (d) 3RCH 3. Acetophenone is prepared from [CPMT 2003] (a) Rosenmund reaction (b) Sandmayer reaction (c) Wurtz reaction (d) Friedel craft reaction 4. Compound which gives acetone on ozonolysis [UPSEAT 2003] (a) 33 CHCHCHCH  (b) 2323 )()( CHCCCH  (c) 256 CHCHHC  (d) 23 CHCHCH  5. , 2 522 || 3 A OH NaOH HCOOCCH O CCH   product ‘A’ in the reaction is [RPMT 2003] (a) COOHCH3 (b) OHHC 52 (c) 33COCHCH (d) CHOHC 52 6. Which one of the following compounds is prepared in the laboratory from benzene by a substitution reaction [EAMCET 2003] (a) Glyoxal (b) Cyclohexane (c) Acetophenone (d) Hexabromo cyclohexane 7. Ketones )( 1 || R O CR  where  1RR alkyl group. It can be obtained in one step by [CBSE PMT 1997] (a) Hydrolysis of esters (b) Oxidation of primary alcohol (c) Oxidation of secondary alcohol (d) Reaction of acid halide with alcohols 8. Predict the product ‘B’ in the sequence of reaction BACHHC NaOH HgSO SOH    4 42%30 [CBSE PMT 2001] (a) COONaCH3 (b) COOHCH3 (c) CHOCH 3 (d) CHOCH OH CHCH 2 | 3  9. ;3 / 2 3 4 HClCHOCHCOClCH BaSOPd H  The above reaction is called [JIPMER 1997] (a) Reimer-Tiemann reaction (b) Cannizzaro reaction (c) Rosenmund reaction (d) Reformatsky reaction 10. The oxidation of toluene to benzaldehyde by chromyl chloride is called [CBSE PMT 1996; AFMC 1998, 99; AIIMS 2000; JIPMER 2001; AFMC 2001; DCE 2004] (a) Cannizzaro reaction (b) Wurtz reaction (c) Etard reaction (d) Reimer-Tiemann reaction 11. From which of the following tertiary butyl alcohol is obtained by the action of methyl magnesium iodide [MP CET 2000] (a) HCHO (b) CHOCH 3 (c) 33COCHCH (d) 2CO 12. Catalyst used in Rosenmund reduction is[Bihar MEE 1997] (a) Pd / 4BaSO (b) Zn-Hg couple (c) 4LiAlH (d) 2/ HNi 13. OH R CHCCHCH 2 23  Butanone, R is[BHU 2003] (a) Hg (b) 4KMnO (c) 3KClO (d) 722 OCrK 14. Dry heating of calcium acetate gives [DPMT 1979, 81, 96; NCERT 1981; KCET 1993; Bihar CEE 1995; MNR 1986; MP PMT 1997; MP PET 1993, 95; JIPMER 2002; AIIMS 1996; CPMT 1982, 86, 96, 2003; RPMT 2002] (a) Acetaldehyde (b) Ethane (c) Acetic acid (d) Acetone 15. Identify the product C in the series CBACNCH HNOOHHCNa     reagent sTollen'/ 3 252 [MP PET 1999] (a) COOHCH 3 (b) NHOHCHCH 23 (c) 23CONHCH (d) CHOCH 3 16. Acetophenone is prepared by the reaction of which of the following in the presence of 3AlCl catalyst [AIIMS 1996] (a) Phenol and acetic acid (b) Benzene and acetone (c) Benzene and acetyl chloride (d) Phenol and acetone 17. Isopropyl alcohol on oxidation gives [RPMT 1997; BHU 1997] (a) Acetone (b) Acetaldehyde (c) Ether (d) Ethylene 18. On heating calcium acetate and calcium formate, the product formed is [DPMT 1984; EAMCET 1985; MP PMT 1996, 92; KCET 1990; CPMT 1979, 82, 84; BIT 1992; RPET 2000] (a) 33COCHCH (b) CHOCH3 (c) 3CaCOHCHO  (d) 33 CaCOCHOCH  19. Which of the following compound gives a ketone with Grignard reagent [CPMT 1988; MP PET 1997] (a) Formaldehyde (b) Ethyl alcohol (c) Methyl cyanide (d) Methyl iodide 20. In the Rosenmund's reduction, 4BaSO taken with catalyst Pd acts as (a) Promotor (b) Catalytic poison (c) Cooperator (d) Absorber 1282 Aldehydes and Ketones [SCRA 2001] (a) 2 reduction sClemenson' CHOC   (b) CHOHOC   reductionKishner -Wolf (c) CHOCOCl   reduction sRosenmund' (d) CHONC   reduction Stephen 11. Which of the following gives aldol condensation reaction [CPMT 2001] (a) OHHC 56 (b) 56 || 56 HC O CHC  (c) 3 || 23 CH O CCHCH  (d) 3 || 33 )( CH O CCCH  12. Which of the following products is formed when benzaldehyde is treated with MgBrCH3 and the addition product so obtained is subjected to acid hydrolysis [Haryana CEET 2000] (a) Secondary alcohol (b) A primary alcohol (c) Phenol (d) Tert-Butyl alcohol 13. Aldol condensation will not be observed in[GATE 2001] (a) Chloral (b) Phenyl acetaldehyde (c) Hexanal (d) Ethanol 14. Which of the following compounds containing carbonyl group will give coloured crystalline compound with [Kerala (Med.) 2001] (a) COClCH3 (b) 33COCHCH (c) )( 523 HOCCOCH (d) 23CONHCH (e) COOHHCHO )( 46 15. Which of the following organic compounds exhibits positive Fehling test as well as iodoform test [MP PET 1994; KCET 2001] (a) Methanal (b) Ethanol (c) Propanone (d) Ethanal 16. Which of the following compound will undergo self aldol condensation in the presence of cold dilute alkali [CBSE PMT 1994] (a) CHOHC 56 (b) CHOCHCH 23 (c) CHOCCH  (d) CHOCHCH 2 17. Acetaldehyde when treated with dilute NaOH gives [EAMCET 1998] (a) OHCHCH 23 (b) COOHCH 3 (c) CHOCH OH CHCH  2 | 3 (d) 33 CHCH  18. CHOHC 52 and COCH 23 )( can be distinguished by testing with [EAMCET 1998; CPMT 1994, 97; MP PET 1995; MP PMT 1996; RPMT 1997, 99] (a) Phenyl hydrazine (b) Hydroxylamine (c) Fehling solution (d) Sodium bisulphite 19. Which of the following will undergo aldol condensation [IIT 1998] (a) Acetaldehyde (b) Propanaldehyde (c) Benzaldehyde (d) Trideuteroacetaldehyde 20. Which of the following oxidation reactions can be carried out with chromic acid in aqueous acetone at Co105  [Roorkee Qualifying 1998] (a)  3 | 323 )( CH OH CHCCCHCH (b)  OHCHCHCHCHCH 2323 )( CHOCHCHCHCH 323 )( (c) COOHHCCHHC 56356  (d) CHOCHCHOHCHCHCH 3232323 )()(  21. Acetaldehyde cannot show [AIIMS 1997] (a) Iodoform test (b) Lucas test (c) Benedict's test (d) Tollen's test 22. Benzaldehyde NaOH [CPMT 1997, 2001; CBSE PMT 1999; Pb. PMT 1999] (a) Benzyl alcohol (b) Benzoic alcohol (c) Hydrobenzamide (d) Cinnamic acid 23. The following reagent converts COCHOHC 56 to CHOHCOONaHC 56 [Roorkee Qualifying 1998] (a) Aq. NaOH (b) Acidic 322 OSNa (c) 4242 / SOHCrONa (d) HClNaNO /2 24. Benzyl alcohol and sodium benzoate is obtained by the action of sodium hydroxide on benzaldehyde. This reaction is known as [KCET 2005] (a) Perkin’s reaction (b) Cannizzaro’s reaction (c) Sandmeyer’s reaction (d)Claisen condensation 25. To distinguish between formaldehyde and acetaldehyde, we require [Orissa PMT 1987] (a) Tollen's reagent (b) Fehling's solution (c) Schiff's reagent (d) Caustic soda solution 2NHNH 2NO NO2 3323 || )( CHCCCCHCH O  Aldehydes and Ketones 1283 26. Which of the following does not give iodoform test [AIIMS 1992; MP PMT 1990, 96; CET Pune 1998 DPMT 1981; CPMT 1976] (a) OHCHCH 23 (b) OHCH3 (c) CHOCH3 (d) 3PhCOCH 27. Which of the following will not give iodoform test [Kurukshetra CEE 1991; Bihar CEE 1995; CBSE PMT 1998; MP PMT 2004] (a) Ethanal (b) Ethanol (c) 2-propanone (d) 3-pentanone 28. Which of the following will not give the iodoform test [MNR 1994] (a) Acetophenone (b) Ethanal (c) Benzophenone (d) Ethanol 29. Haloform test is given by the following substance [EAMCET 1988] (a) HCHO (b) COCH 23)( (c) 33OCHCH (d) ClCHCH 23 30. Dimethyl ketones are usually characterised through [MNR 1992] (a) Tollen's reagent (b) Iodoform test (c) Schiff's test (d) Benedict's reagent 31. The light yellow compound produced when acetone reacts with iodine and alkali, is[MP PMT 1992; EAMCET 1993] (a) ICHCOCH 23 .. (b) ICH3 (c) 3CHI (d) None of these 32. If formaldehyde and KOH are heated, then we get [MP PET 1999; KCET 2000] (a) Acetylene (b) Methane (c) Methyl alcohol (d) Ethyl formate 33. Which of the following reagent reacts differently with CHOCHHCHO 3, and 33COCHCH [MP PET 1999] (a) HCN (b) 22 NHNH (c) OHNH 2 (d) 3NH 34. Acetaldehyde reacts with MgClHC 52 the final product is [Pb. CET 1985] (a) An aldehyde (b) A ketone (c) A primary alcohol (d) A secondary alcohol 35. Treatment of propionaldehyde with dilute NaOH solution gives [MNR 1992] (a) 32223 CHCHCOOCHCHCH (b) CHOCHCHOHCHCHCH )( 323 (c) CHOCHCHOHCHCHCH 2223 (d) CHOCHCOCHCHCH 2223 36. Aldol condensation of acetaldehyde involves the formation of which of the following intermediate[Pb. CET 1986] (a) Acetate ion (b) A carbanion (c) A carbonium ion (d) A free radical 37. 232333 )()(3 CHCCHCOCHCCHCOCHCH HCl   This polymer (B) is obtained when acetone is saturated with hydrogen chloride gas, B can be [CBSE PMT 1989] (a) Phorone (b) Formose (c) Diacetone alcohol (d) Mesityl oxide 38. Aromatic aldehydes undergo disproportionation in presence of sodium or potassium hydroxide to give corresponding alcohol and acid. The reaction is known as [MNR 1987] (a) Wurtz's reaction (b) Cannizzaro reaction (c) Friedel-Craft's reaction (d) Claisen reaction 39. m-chlorobenzaldehyde on reaction with conc. KOH at room temperature gives [IIT-JEE 1991] (a) Potassium m-chlorobenzoate and m-hydroxy benzaldehyde (b) m-hydroxy benzaldehyde and m-chlorobenzyl alcohol (c) m-chlorobenzyl alcohol and m-hydroxy benzyl alcohol (d) Potassium m-chlorobenzoate and m- chlorobenzyl alcohol 40. Which of the following does not give yellow precipitate with KINaOH  [MP PMT 1997] (a) Acetone (b) Acetaldehyde (c) Benzaldehyde (d) Acetophenone 41. The alkaline 4CuSO containing sodium potassium tartrate does not react with [MP PMT 1997] (a) CHOCH 3 (b) CHOHC 52 (c) CHOCHHC 256 (d) CHOHC 56 42. Correct order of reactivity of 3523 , COCHHCCHOCH and 33COCHCH is[MP PMT 1991] (a) 523333 HCOCCHCOCHCHCHOCH  (b) CHOCHCOCHCHCOCHHC 333352  (c) 352333 COCHHCCHOCHCOCHCH  (d) CHOCHCOCHHCCOCHCH 335233  43. One mole of an organic compound requires 0.5 mole of oxygen to produce an acid. The compound may be [NCERT 1981] (a) Alcohol (b) Ether (c) Ketone (d) Aldehyde 44. Aldehydes can be oxidised by [NCERT 1983] (a) Tollen's reagent (b) Fehling solution (c) Benedict solution (d) All of these 45. Silver mirror is a test for[DPMT 1983; CBSE PMT 1988] (a) Aldehydes (b) Thio alcohols (c) Amines (d) Ethers 46. CHCHOCHCH 3 is oxidised to CHCOOHCHCH 3 using [NCERT 1978] (a) Alkaline 4KMnO (b) Selenium dioxide (c) Ammoniacal 3AgNO (d) All of these 1284 Aldehydes and Ketones 47. Which of the following does not turn Schiff's reagent to pink [DPMT 1981; CPMT 1989] (a) Formaldehyde (b) Benzaldehyde (c) Acetone (d) Acetaldehyde 48. Fehling's test is positive for [KCET 1993] (a) Acetaldehyde (b) Benzaldehyde (c) Ether (d) Alcohol 49. Acetaldehyde and acetone differ in their reaction with [KCET 1989] (a) Sodium bisulphite (b) Ammonia (c) Phosphorus pentachloride (d) Phenyl hydrazine 50. The final product formed when acetaldehyde is reduced with sodium and alcohol is [BHU 1976] (a) Ethylene (b) Ethyl alcohol (c) Ethene (d) All of these 51. The compound obtained by the reduction of propionaldehyde by amalgamated zinc and concentrated HCl is [MP PMT 1983] (a) Propanol (b) Propane (c) Propene (d) All of these 52. Formaldehyde when treated with KOH gives methanol and potassium formate. The reaction is known as [MP PET 1997] (a) Perkin reaction (b) Claisen reaction (c) Cannizzaro reaction (d) Knoevenagel reaction 53. Aldehydes and ketones give addition reaction with [KCET 1992] (a) Hydrazine (b) Phenyl hydrazine (c) Semicarbazide (d) Hydrogen cyanide (e) All of these 54. Acetaldehyde reacts with [CBSE PMT 1991] (a) Electrophiles only (b) Nucleophiles only (c) Free radicals only (d) Both electrophiles and nucleophiles 55. The typical reactions of aldehyde is [Pb. CET 1986] (a) Electrophilic addition (b)Nucleophilic substitution (c) Nucleophilic addition (d)Nucleophilic elimination 56. Which will not give acetamide on reaction with ammonia [CPMT 1985] (a) Acetic acid (b) Acetyl chloride (c) Acetic anhydride (d) Methyl formate 57. The addition of HCN to carbonyl compounds is an example of [Haryana CEET 2000] (a) Nucleophilic substitution (b) Electrophilic addition (c) Nucleophilic addition (d) Electrophilic substitution 58. Which of the following reagents is used to distinguish acetone and acetophenone[RPMT 2002; KCET 1998] (a) 3NaHSO (b) Grignard reagent (c) 42SONa (d) ClNH4 59. The product formed by the reaction of chlorine with benzaldehyde in the absence of a catalyst is [Tamil Nadu CET 2002] (a) Chlorobenzene (b) Benzyl chloride (c) Benzoyl Chloride (d) o- Chlorobenzaldehyde 60. Which of the following compound is resistant to nucleophilic attack by hydroxyl ions [CBSE PMT 1998; KCET (Med.) 2001; AFMC 2001] (a) Methyl acetate (b) Acetonitrile (c) Dimethyl ether (d) Acetamide 61. Glucose molecule reacts with X number of molecules of phenylhydrazine to yield osazone. The value of X is [CBSE PMT 1998] (a) One (b) Two (c) Three (d) Four 62. In which of the following reactions aromatic aldehyde is treated with acid anhydride in presence of corresponding salt of the acid to give unsaturated aromatic acid [BHU 1998, KCET (Med.) 2001] (a) Friedel-Craft's reaction (b) Perkin reaction (c) Wurtz reaction (d) None of these 63.    H HgMgCH O CCH / 3 || 32 Product, product in the reaction is [RPMT 2003] (a) 3 | 3 | 3 | | 3 CH H OH CC CH OH CCH  (b) 3 |||| 3 CH O CO O CCH  (c) 3 || 3 CH OH CH OH CHCH  (d) None of these 64. Cinnamic acid is formed when CHOHC 56 condenses with OCOCH 23 )( in presence of[Orissa JEE 2003] (a) Conc. 42SOH (b) Sodium acetate (c) Sodium metal (d) Anhydrous 2ZnCl 65. A mixture of benzaldehyde and formaldehyde on heating with aqueous NaOH solution gives [IIT-JEE (Screening) 2001] (a) Benzyl alcohol and sodium formate (b) Sodium benzoate and methyl alcohol (c) Sodium benzoate and sodium formate (d) Benzyl alcohol and methyl alcohol 66. The reaction,     OHorH OHHCOCH O CCH 523 || 3 Aldehydes and Ketones 1287 105. When 33COCHCH reacts with 2Cl and NaOH, which of the following is formed [CPMT 1996] (a) 3CHCl (b) 4CCl (c) 22 HCCl (d) ClCH 3 106. Which gives difference between aldehyde and ketone [CPMT 1994] (a) Fehling's solution (b) Tollen's reagent (c) Schiff's reagent (d) Benedict's solution (e) All of these 107. Aldehyde turns pink with [Bihar MEE 1997] (a) Benedict solution (b) Schiff reagent (c) Fehling solution (d) Tollen's reagent (e) Mollisch reagent 108. Which of the following would undergo aldol condensation [MP PMT 1986; BHU 1995] (a) CHOCCl .3 (b) CHO CH CH CCH 3 | 3 | 3  (c) CHOCHCH .. 23 (d) HCHO 109. The reaction of acetaldehyde with conc. 4KMnO gives [DPMT 1982; AIIMS 1996] (a) COOHCH3 (b) OHCHCH 23 (c) HCHO (d) OHCH3 110. When acetaldehyde is heated with Tollen's reagent, following is obtained[CPMT 1989; MP PET/PMT 1988] (a) Methyl alcohol (b) Silver acetate (c) Silver mirror (d) Formaldehyde 111. Boiling point of acetone is [CPMT 1975, 89] (a) Co56 (b) Co60 (c) Co100 (d) Co90 112. Urotropine is (a) Hexamethylene tetramine (b) Hexaethylene tetramine (c) Hexamethylene diamine (d) None of these 113. Magenta is [DPMT 1982; Kurukshetra CEE 1998] (a) Alkaline phenolphthalein (b) Methyl red (c) p-rosaniline hydrochloride (d) Red litmus 114. An aldehyde on oxidation gives [CPMT 1973, 03; DPMT 1983; Manipal MEE 1995] (a) An alcohol (b) An acid (c) A ketone (d) An ether 115. The reaction of an aldehyde with hydroxylamine gives a product which is called[MP PET 1993; AFMC 2002] (a) Aminohydroxide (b) Hydrazone (c) Semicarbazone (d) Oxime 116. Cannizzaro reaction is not shown by [BHU 1980; IIT 1983; KCET 1993; Bihar MEE 1995; RPMT 1997, 2000, 02] (a) HCHO (b) CHOHC 56 (c) CHOCH 3 (d) All of these 117. When acetone is heated with hydroxylamine, the compound formed is [MP PMT 1993] (a) Cyanohydrin (b) Oxime (c) Semicarbazone (d) Hydrazone 118. The product of the reaction between ammonia and formaldehyde is [MP PMT 1993] (a) Urotropine (b) Formamide (c) Paraformaldehyde (d) Methanol 119. Which of the following products is obtained by the oxidation of propionaldehyde [CPMT 1989] (a) Acetic acid (b) Formic acid and acetic acid (c) Propanoic acid (d) n-propyl alcohol 120. When acetaldehyde reacts with ,5PCl the resulting compound is [MP PMT 1992, 93] (a) Ethyl chloride (b) Ethylene chloride (c) Ethylidene chloride (d) Trichloro acetaldehyde 121. Benzaldehyde and acetaldehyde can be differentiated by (a) HCN (b) OHNH 2 (c) Hydrazine (d) NaOH solution 122. In the presence of a dilute base CHOHC 56 and CHOCH 3 react together to give a product. The product is [MP PET 1994] (a) 356 CHHC (b) OHCHCHHC 2256 (c) OHCHHC 256 (d) CHCHOCHHC 56 123. Grignard's reagent reacts with ethanal (acetaldehyde) and propanone to give (a) Higher aldehydes with ethanal and higher ketones with propanone (b) Primary alcohols with ethanal and secondary alcohols with propanone (c) Ethers with ethanal and alcohols with propanone (d) Secondary alcohols with ethanal and tertiary alcohols with propanone 124. Base catalysed aldol condensation occurs with [IIT-JEE 1991] (a) Benzaldehyde 1288 Aldehydes and Ketones (b) 2, 2-dimethyl propionaldehyde (c) Acetaldehyde (d) Formaldehyde 125. Benzaldehyde reacts with ammonia to form [CPMT 1989; AFMC 1998] (a) Benzaldehyde ammonia (b) Urotropine (c) Hydrobenzamide (d) Aniline 126. Glucose + Tollen's reagent  Silver mirror shows [CPMT 1997] (a) Presence of acidic group (b) Presence of alkaline group (c) Presence of ketonic group (d) Presence of aldehyde group 127. Fehling solution is [MP PMT 1989] (a) Ammoniacal cuprous chloride solution (b) Acidified copper sulphate solution (c) Copper sulphate and sodium hydroxide + Rochelle salt (d) None of these 128. Reduction of an aldehyde produces [MP PMT 1994; MP PET 2001] (a) Primary alcohol (b) Monocarboxylic acid (c) Secondary alcohol (d) Tertiary alcohol 129. Which of the following on reaction with conc. NaOH gives an alcohol [MP PET 1996] (a) Methanal (b) Ethanal (c) Propanal (d) Butanal 130. Schiff's reagent is [MP PMT 1989] (a) Magenta colour solution decolourised with sulphurous acid (b) Ammoniacal cobalt chloride solution (c) Ammoniacal manganese sulphate solution (d) Magenta solution decolourised with chlorine 131. Pyrolysis of acetone gives OCCH 2 called (a) Methylene oxide (b) Methyl carbon monoxide (c) Ketene (d) Methone 132. Which one of the following on oxidation will not give a carboxylic acid with the same number of carbon atoms [CBSE PMT 1992; MP PET 1996] (a) 33COCHCH (b) CHOCHCCl 23 (c) OHCHCHCH 223 (d) CHOCHCH 23 133. Acetal is obtained by reacting in the presence of dry HCl and alcohol with [MP PET 1996] (a) Aldehyde (b) Ketone (c) Ether (d) Carboxylic acid 134. The reagent with which both aldehyde and acetone react easily is [CPMT 1973, 74, 89; BIT 1992] (a) Fehling's reagent (b) Grignard reagent (c) Schiff's reagent (d) Tollen's reagent 135. Phenylmethanol can be prepared by reducing the benzaldehyde with [CBSE PMT 1997] (a) BrCH 3 (b) Zn and HCl (c) BrCH 3 and Na (d) ICH 3 and Mg 136. Which of the following is used in the manufacture of thermosetting plastics (a) Formaldehyde (b) Acetaldehyde (b) Acetone (d) Benzaldehyde 137. Which compound undergoes iodoform reaction [DPMT 1984; CPMT 1989] (a) HCHO (b) CHOCH3 (c) OHCH3 (d) COOHCH3 138. Which does not react with Fehling solution[MNR 1983, 93] (a) Acetaldehyde (b) Benzaldehyde (c) Glucose (d) Formic acid 139. Which of the following compound will react with ethanolic KCN [IIT-JEE 1984] (a) Ethane (b) Acetyl chloride (c) Chlorobenzene (d) Benzaldehyde 140. Schiff's reagent gives pink colour with [EAMCET 1980; MP PMT 2000] (a) Aldehydes (b) Ethers (c) Ketones (d) Carboxylic acid 141. Acetaldehyde reacts with 2Cl (in excess) to give [MP PMT 1997] (a) Chloral (b) Chloroform (c) Acetic acid (d) Trichloroacetic acid 142. The compound which reacts with Fehling solution is [CPMT 1989] (a) COOHHC 56 (b) HCOOH (c) CHOHC 56 (d) 32ClCHCH 143. Which one of the following undergoes reaction with 50% sodium hydroxide solution to give the corresponding alcohol and acid [AIEEE 2004] (a) Butanal (b) Benzaldehyde (c) Phenol (d) Benzoic acid 144. Which one of the following is reduced with zinc and hydrochloric acid to give the corresponding hydrocarbon [AIEEE 2004] (a) Acetamide (b) Acetic acid (c) Ethyl acetate (d) Butan–2–one Aldehydes and Ketones 1289 145. Three molecules of acetone in the presence of dry HCl form [MP PET 2004] (a) Mesitylene (b) Phorone (c) Glyoxal (d) Mesityl oxide 146. Aldehydes and ketones can be reduced to corresponding hydrocarbons by [Kerala PMT 2004] (a) Refluxing with water (b) Refluxing with strong acids (c) Refluxing with soda amalgam and water (d) Refluxing with zinc amalgam and concentrated HCl (e) Passing the vapour under heated 2PbO 147. Acetone reacts with iodine to form iodoform in the presence of [BHU 2004; CPMT 2004] (a) 3CaCO (b) NaOH (c) KOH (d) 3MgCO 148. Cyanohydrin of which of the following forms lactic acid [MHCET 2003] (a) CHOCHCH 23 (b) CHOCH 3 (c) HCHO (d) 33COCHCH 149. Which of the following is used to detect aldehydes [MHCET 2004] (a) Million's test (b) Tollen's reagent (c) Neutral ferric chloride solution (d) Molisch's test 150. Which of the following aldehydes give red precipitate with Fehling solution ? [MHCET 2004] (a) Benzaldehyde (b) Salicylaldehyde (c) Acetaldehyde (d) None of these 151. ACHCOCHCCHA 323 )(  is [MHCET 2004] (a) Acetone (b) Acetaldehyde (c) Propionaldehyde (d) Formaldehyde 152. The aldehyde which react with NaOH to produce an alcohol and sodium salt is [Pb. PMT 2004] (a) HCHO (b) CHOCH 3 (c) CHOCHCH 23 (d) CHOCHCHCH 223 153. Acetaldehyde and Acetone can be distinguished by [DCE 2003] (a) Iododorm test (b) Nitroprusside test (c) Fehling's solution test (d) DNP test 154. COOHCHOHCHOOCH OH    2 The reaction given is [DCE 2003] (a) Aldol condensation (b) Knovengel reaction (c) Cannizzaro reaction (d) None of these 155. The order of susceptibility of nucleophilic attack on aldehydes follows the order [DCE 2002] (a) 1° > 3° > 2° (b) 1° > 2° > 3° (c) 3° > 2° > 1° (d) 2° > 3° > 1° 156. In Wolf-Kishner reduction, the carbonyl group of aldehydes and ketones is converted into [Pb. CET 2000] (a) 2CH group (b) 3CH group (c) OHCH 2 group (d) CHOH group 157. Which of the following react with 3NaHSO [Pb. CET 2003] (a) 33COCHCH (b) CHOCH 3 (c) HCHO (d) All of these 158. Fehling solution is [Pb. CET 2003] (a) 4CuSO + lime (b) )(4 aqNaOHCuSO  (c) 324 CONaCuSO  (d) None of these 159. Wolf kishner reduction, reduces [Pb. CET 2003] (a) COOH group (b) CC  – group (c) CHO group (d) O group 160. A compound has a vapour density of 29. On warming an aqueous solution of alkali, it gives a yellow precipitate. The compound is [DPMT 2004] (a) CHOCHCH 23 (b) 33CHOHCHCH (c) 33COCHCH (d) COOHCHCH 23 161. Which responds to +ve iodoform test ?[Orissa JEE 2004] (a) Butanol (b) Butan-1-al (c) Butanol-2 (d) 3-pentanone 162. The correct order of reactivity of PhMgBr with [IIT-JEE (Screening) 2004] O PhCPh ||  O HCCH || 3  O CHCCH || 33  is (I) (II) (III) (a) (I) > (II) > (III) (b) (III) > (II) > (I) (c) (II) > (III) > (I) (d) (I) > (III) > (II) 163. The pair of compounds in which both the compounds give positive test with Tollen's reagent is [IIT-JEE (Screening) 2004] (a) Glucose and Sucrose (b) Fructose and Sucrose (c) Acetophenone and Hexanal (d) Glucose and Fructose 164. The most appropriate reagent to distinguish between acetaldehyde and formaldehyde is[UPSEAT 2004] (a) Fehling's solution (b) Tollen's reagent (c) Schiff's reagent (d) Iodine in presence of base 165. Silver mirror test can be used to distinguish between 1292 Aldehydes and Ketones (a) 322 CHCOCHICH (b) 33COOCOCHCH (c) 23CONHCH (d) 323 )( CHCHOHCHCH 15. The product of acid hydrolysis of P and Q can be distinguished by [IIT-JEE (Screening) 2003] (a) Lucas Reagent (b) 2,4-DNP (c) Fehling’s Solution (d) 3NaHSO 16. On vigorous oxidation by permanganate solution 32223)( CHCHCHCHCCH  gives [AIEEE 2002] (a) 32 | 3 | | 3 CHCH OH CH OH CH CCH  (b) 3 32 3 CH COOHCHHCHCO CH  (c) 3 223 3 CH OHCHCHCHCHOH CH  (d) 3 23 3 CH COOHCHCHOC CH  17. Which of the following reactions give benzo phenone [Roorkee Qualifying 1998] (a) OH AlCl CClHC 2 3 (ii) (i) 4662   (b)   3 5666 AlCl COClHCHC (c)   Heat 56463 HCOCHCCHo (d) C Cu o HCOCHCHOOCo 260 5646  18. Aldehyde and ketones can decolourize by[CPMT 2003] (a) Bromine water (b) Quick lime (c) dil. 42SOH (d) None of these 19. Which of the following statements regarding chemical properties of acetophenone are wrong (1) It is reduced to methyl phenyl carbinol by sodium and ethanol (2) It is oxidised to benzoic acid with acidified 4KMnO (3) It does not undergo iodoform electrophilic substitution like nitration at meta position (4) It does not undergo iodoform reaction with iodine and alkali [Tamil Nadu CET 2001] (a) 1 and 2 (b) 2 and 4 (c) 3 and 4 (d) 1 and 3 20. The product(s) obtained via oxymercuration )( 424 SOHHgSO  of 1-butyne would be [IIT-JEE 1999] (a) 323 COCHCHCH (b) CHOCHCHCH 223 (c) HCHOCHOCHCH 23 (d) HCOOHCOOHCHCH 23 21. The most reactive compound towards formation of cyanohydrin on treatment with KCN followed by acidification is [GATE 2001] (a) Benzaldehyde (b) p-Nitrobenzaldehyde (c) Phenyl acetaldehyde (d) p- Hydroxybenzaldehyde 22. The key step in cannizzaro’s reaction is the intermolecular shift of [Orissa JEE 2003] (a) Proton (b) Hydride ion (c) Hydronium ion (d) Hydrogen bond 23. Benzophenone does not react with [BHU 2003] (a) 2RNH (b) 3SO (c) NaOH (d) 32CONa 24. The most suitable reagent for the conversion of RCHOOHRCH 2 is [AIIMS 2004] (a) 4KMnO (b) 722 OCrK (c) 3CrO (d) PCC (Pyridine chloro chromate) 25. The conversion of acetophenone to acetanilide is best accomplished by using : [UPSEAT 2004] (a) Backmann rearrangement (b) Curtius rearrangement (c) Lossen rearrangement (d) Hofmann rearrangement 26. Which of the following will not give iodoform test ? [UPSEAT 2004] (a) Isopropyl alcohol (b) Ethanol (c) Ethanal (d) Benzyl alcohol 27. MeO    OH COONaCH XCHO 3 3)( CHCOOHCH  The compound (X) is [IIT-JEE 2005] (a) COOHCH 3 (b) COOHBrCH 2 3OCOCH 3CH 3OCOCH CH3 CHP 2 Q = Aldehydes and Ketones 1293 (c) OCOCH 23 )( (d) COOHCHO  28. The major organic product formed from the following reaction [CBSE PMT 2005] (a) (b) (c) (d) 29. Products of the following reaction are... )2( )1( 323 3 Hydrolysis O CHCHCCCH   [CBSE PMT 2005] (a) CHOCHCHCHOCH 233  (b) CHOCHCHCOOHCH 233  (c) 323 CHHOOCCHCOOHCH  (d) 23 COCOOHCH  30. A compound, containing only carbon, hydrogen and oxygen, has a molecular weight of 44. On complete oxidation it is converted into a compound of molecular weight 60. The original compound is [KCET 2005] (a) An aldehyde (b) An acid (c) An alcohol (d) an ether Read the assertion and reason carefully to mark the correct option out of the options given below : (a) If both assertion and reason are true and the reason is the correct explanation of the assertion. (b) If both assertion and reason are true but reason is not the correct explanation of the assertion. (c) If assertion is true but reason is false. (d) If the assertion and reason both are false. (e) If assertion is false but reason is true. 1. Assertion : Acetic acid does not undergo haloform reaction. Reason : Acetic acid has no alpha hydrogens. [IIT 1998] 2. Assertion : Benzonitrile is prepared by the reaction of chlorobenzene with potassium cyanide. Reason : Cyanide (CN–) is a strong nucleophile. [IIT 1998] 3. Assertion : Lower aldehyde and ketones are soluble in water but the solubility decreases as molecular mass increases. Reason : Aldehydes and ketones can be distinguished by Tollen's reagent.[AIIMS 1994] 4. Assertion : Acetaldehyde on treatment with alkaline gives aldol. Reason : Acetaldehyde molecules contains  hydrogen atom. [AIIMS 1997] 5. Assertion : Acetylene on treatment with alkaline 4KMnO produce acetaldehyde. Reason : Alkaline 4KMnO is a reducing agent. [AIIMS 2000] 6. Assertion : Acetophenone and benzophenone can be distinguished by iodoform test. Reason : Acetophenone and benzophenone both are carbonyl compounds. [AIIMS 2002] 7. Assertion : Isobutanal does not give iodoform test Reason : It does not have -hydrogen.[AIIMS 2004] 8. Assertion : Benzaldehyde is more reactive than ethanol towards nucleophilic attack. Reason : The overall effect of –I and +R effect of phenyl group decreases the electron density on the carbon atom of OC  group in benzaldehyde. 9. Assertion : Aldol condensation can be catalysed both by acids and bases. Reason : -Hydroxy aldehydes or ketones readily undergo acid catalysed dehydration. 10. Assertion : Ketones are less reactive than aldehydes. Reason : Ketones do not give schiff's test. 11. Assertion : Oximes are less acidic than hydroxyl amine. Reason : Oximes of aldehydes and ketones show geometrical isomerism. 12. Assertion : The bond energy of OC  is less than > CC  < in alkenes. Reason : The carbon atom in carbonyl group is 2sp hybridised. 13. Assertion :  0CR is more stable than 0 CR . Reason : Resonance in carbonyl compound provides C+ and O–. 14. Assertion : Formaldehyde cannot be prepared by Rosenmund's reduction. OHiiiLiAlHii NHCH 24 23 )()( (i)   ... is O OH 3NCH H H NCH 3 3.NHCHO OH 3NCH H 1294 Aldehydes and Ketones Reason : Acid chlorides can be reduced into aldehydes with hydrogen in boiling xylene using palladium or platinum as a catalyst supported on barium sulphate. This is known as Rosenmund's reduction. 15. Assertion : CHOCH 3 reacts with 3NH to form urotropine. Reason : Urotropine is used as medicine in case of urinary troubles. 16. Assertion : -Hydrogen atoms in aldehydes and ketones are acidic. Reason : The anion left after the removal of - hydrogen is stabilized by inductive effect. 17. Assertion : 2, 2–Dimethyl propanal undergoes Cannizzaro reaction with concentrated NaOH. Reason : Cannizzaro is a disproportionation reaction. 18. Assertion : Benzaldehyde undergoes aldol condensation. Reason : Aldehydes that do not have – hydrogen undergo aldol condensation. Introduction 1 a 2 b 3 a 4 c 5 a 6 c 7 b 8 b 9 a 10 b 11 b 12 d 13 d 14 b 15 a 16 c 17 c 18 c Aldehydes and Ketones 1295 OH R NHCHCR | | ' 22 5. (c) Reduction of OC  to 2CH can be carried out with Wolf Kischner reduction. 6. (d)  H2 on reduction it gives benzylalcohol and not phenol. 9. (c) neAcetopheno 356 ][ nolPhenyletha1 356 COCHHCCHOHCHHC O   HClCOCHHCCOClCHHC   356 reaction scraft'Friedel 366 10. (b) Wolf-Kishner reduction does not convert CO to CHOH but converts it to 2CH . 11. (c) Although both 323 COCHCHCH and 333)( CCOCHCH contain -hydrogen, yet 333)( CCOCHCH does not undergo Aldol condensation due to steric hindrance. 12. (a) Alcohol2 356 /deBenzaldehy 56 )( 2 3     CHOHCHHCCHOHC OHH MgBrCH 13. (a) Chloral ,3CHOCCl has no -hydrogen atom and hence does not undergo aldol condensation. 14. (b) Among the given compounds only acetone gives crystalline coloured derivative with 2, 4 DNP. 15. (d) Ethanal among the given compounds gives positive iodoform test. 17. (c) CHOCH OH HCCHCHOCH NaOH 2 | 3 dil. 32  18. (c) OHOCuOHCuCHOHC pptd 2 Re 2 2 52 352    COOHC 52 reactionNo52 2 33   OHCuCOCHCH 19. (abd)Deuterium behaves like H and hence trideuteroacetaldehyde also undergoes aldol condensation but benzaldehyde does not since it has no -hydrogen. 21. (b)   HClZnClo /2alcoholPrimary1 White turbidity only heating   HClZnClo Alcohol /22 White turbidity after 5 min heating   HClZnClo /2Alcohol3 easily in seconds 24. (b) Benzaldehyde on treatment with 50% aqueous or ethanolic alkali solution undergoes Cannizzaro’s reaction like HCHO (no  - hydrogen atom) i.e., one molecule is oxidised and one is reduced with the formation of benzoic acid and benzyl alcohol respectively. COONaHCOHCHHCCHOHC NaOH 56256562   25. (d) HCOONaOHCHHCHO Conc NaOH   3 . 2 It is a Cannizzaro’s reaction. CHOCH OH CHCHCHOCH dil NaOH   2 | 332 It is aldol condensation reaction. 27. (d) 32 || 23 CHCH O CCHCH  do not have O CCH  || 3 group 29. (b) HClCCl O CCHClCH O CCH 33 3 || 323 || 3  O ONaCCHCHClNaOHCCl O CCH  || 333 || 3 30. (b) ONa O CCHCHINaOHI O CHCCH  || 33 ketonedimethyl 2 || 33 3 31. (c) 3CHI is yellow compound when iodine reacts with NaOH and ketone. 32. (c) OHCHHCOOKHCHOHCHO KOH 3  38. (b) 2   NaOHConc. + This reaction is called as Cannizzaro’s reaction. 39. (d) + KOH   .Conc + 41. (d) The solution represented is fehling’s and it has no tendency to oxidise benzaldehyde. 42. (a) Increasing alkyl group the reactivity decreases. 43. (d) RCOOHORCHO  2 2 1 44. (d) All test for Aldehyde because ketone require strong oxidising agent. OHNHAgRCOOHRCHONHAg 2323 42])([2  45. (a) Silver mirror test is the test of aldehyde. 46. (c)  ])([2 233 NHAgCHCHOCHCH OHCHCOOHCHCHNHAg 23342  CHO Benzaldehy de OHCH 2 Benzylalco hol CHO 3CH COONa OHCH3 CHO 3CH Cl CHO 3CH Cl COOK Cl OHCH3 Cl 1296 Aldehydes and Ketones 49. (b) OH NH HCCHNHH O CCH 2 | | 33 || 3  32 3 2 | | 333 || 3 || 2 CH O CCH CH NH CCHNHCH O CCH  50. (b) OHCHCHHCHOCH OHHCNa 23 / 3 522   51. (b) OHCHCHCHHCHOCHCH HCl HgZn 2323 / 23 4   This reaction is called clemmenson’s reduction. 52. (c) In cannizaro’s reaction the one substance is oxidized and other is reduced. HCOOKOHCHHCHOHCHO KOH   3 55. (c) Nucleophilic as addition of 3, NaHSOHCN etc. 57. (c) Addition of HCN to carbonyl compounds is an example of nucleophilic addition. 58. (a) Acetone forms sodium bisulphate adduct but acetophenone does not. Aromatic ketones do not gives addition product with 3NaHSO . 59. (c) HClCOClHCClCHOHC  chlorideBenzoyl 562 deBenzaldehy 56 60. (c) 33 CHOCH    The electron density of oxygen is highly increased therefore resistant its nucleophilic attack. 63. (a) )Pinacol( 3 3 3 3 / Acetone 33 | | | | 2 2 CH OH CHC CH OH CCHCHCOCH OH HgMg   64. (b)   NaCOCH OCOCHCHOHC 23 2356 )( HCHCOCHHC 256  It is Perkin’s reaction. 65. (a) Crossed aldol reaction gives benzyl alcohol and sodium formate.   )( deFormaldehydeBenzaldehy 56 aqNaOH HCHOCHOHC formateSod.alcoholBenzyl 256 HCOONaOHCHHC  66. (d) The substitution of alkoxy group of ester by an alcohol, is called trans-esterification. It occurs in presence of either an acid or base. 67. (a) OHNCHNHHCHO 2 Urotropine 4623 6)(46  68. (a) In HCHO because -Hydrogen atom is absent. 71. (c)   NaCN HC O CHH O CHC alc 56 |||| 56 Benzoin 56 ||| 56 HC O C OH CHHC  72. (d) GlycolKOH NHNH CH O CCH / 3 || 3 22    22323 NOHCHCHCH  75. (a) (Aldol) 2 | 3 dil 32 CHOCH OH CHCHCHOCH NaOH   76. (d) The amount of enolic form is highest (76%) in acetyl acetone because keto group is a much better electron-withdrawing group. OO CCHCCHCH |||| 24%)form, (keto acetoneacety l 323 ⇌ OHO CCHCHCCH ....— ||| (76%) formenolic 33  OHO CHCCHCCH —.... ||| 33  78. (b) 80. (b)  CHOCHHO H C .2 | 82. (c) Aldol 2 | 33 CHOCH OH CHCHCHOCH NaOHdil   OHCHOCHCHCH Heat 23   83. (c) OH CN C R R HCNOC R R  is an example of nucleophilic addition reaction. 84. (a) OH NaOH HCOCCHCHOHC 2 56356    neacetophenoBenzy l 5656 || HC O CCHCHHC  85. (d) HI/P/, Zn/Hg/conc. HCl and ONaHCOHNHNH 5222 //  used to the reduction of  O C || group into  2CH group. 86. (a) OH SOHConc COCHCH 2 42 3 . 333    87. (d)   COONaHCCHOHC NaOH 56 %50 562 OHCHHC 256 It is Cannizzaro’s reaction. 3CH (Mesitylene) CH 3 3CH CHO + COONa CH2OH   NaOH hydeCinnamalde CHOCHCH  Aldehydes and Ketones 1297 88. (a) Because acetone require stronger oxidising agent and hence not oxidized with Fehling solution to give brick red ppt. 89. (d) COOHCHCHOCH NHAg 3 ])([ 3 23   tmirror tesSilver 3NHAg   While acetone do not react. 90. (d) Due to H bonding all are soluble in water. 91. (b) )alcohol2( 3 | | 33 | 3 o CH H OHCCHMgBrCHO H CCH  92. (b)    HOHHCN CNOHCHCHCHOCH /2 33 2)( COOHOHCHCH )(3 93. (a) This reaction is aldol condensation butanalhydroxy3 2 | 3 NaOHdil 32    CHOCH OH CHCHCHOCH 94. (c) ppt OHOCuHCOOOHCuHCHO Red 22 solution Fehling2 352    95. (c) I OH MgOHCHCHMgICHCHOH  233 100. (c)   OH CHO CH CHH O H CCHCH 3 | || | 23  3 | | 23 CH CHCHO OH CHCHCH  101. (c)              OMgI CH HCCHCHOCHMgICH 3 | | 333 Propanol2 23)(3     CHOHCH OH 102. (d) Cannizzaro’s reaction involve self oxidation and self reduction. 103. (a)  NHNHCHOCH 23 NHNCHCH 3 105. (a) 3233 2/2 CHClNaOHClCOCHCH  + HClCOONaCH 32 106. (e) Fehling solution  Alkaline KNaCuSO 4 tartarate Tollen’s reagent  34 AgNOOHNH  Schiff’s reagent  P-rosaniline hydrochloride or magneta Benedict’s solution  Alkaline 4CuSO Citrate ions All these reagents are used to distinguish between aldehydes and ketones. Aldehydes reacts with all these reagents while ketones do not react. 107. (b) ColourlessreagentsSchiff' 2 (Pink)   SO colourPink Aldehyde   108. (c) CHOCHCH   23 aldehydes having H atom can participate in aldol condensation. The H atom attached to  carbon atom are called  -hydrogen. 109. (a) acidAcetic 3 OxidationdeAcetaldehy 3 4 COOHCHCHOCH KMnO   110. (c)  reagentsTollen' 233 ])([2 OHNHAgCHOCH OHNHAgCOONHCH 2 mirrorSilver 343 32  112. (a) It is used as a medicine to treat urinary infections. 113. (c) p-rosaniline hydrochloride.   ClNHC CH NH NH 2 3 2 2 It is used for the identification of aldehydes. 115. (d) Oxime 2 OHNRCHCHOR OHNH    OHOHNCHCHOHNHCHOCH 2 meAcetaldoxi 323  116. (c) Cannizzaro’s reaction is shown by aldehydes in which -H atom is absent. CHOCH3 contains ,3 -H atoms thus, does not show this reaction. 117. (b) Acetoxime 2 3 3 2 3 3 OHOHNC CH CH OHNHOC CH CH  119. (c) acidPropanoic 23 Oxidation Propanal 23 COOHCHCHCHOCHCH   120. (c)  53 PClCHOCH dihalideGem or ChlorideEthylidene 33 POCl Cl Cl CHCH  121. (d) Benzaldehyde gives cannizaro’s reaction whereas acetaldehyde gives aldol condensation. Brady’s reagent (2, 4 – DNP) NO2 NO2 NO2 NO2 Orange crystalline solid CHO COONa CH2OH +   NaOHConc 2 Cannizaro reaction 1300 Aldehydes and Ketones 175. (a) As A reacts with hydroxylamine it means A may be aldehyde or ketone. but it does not react with fehling solution hence A must be a ketone. Secondly it forms iodoform which is a characteristic reaction of methyl ketone. NOH CHCHCHCCH O CHCHCHCCH OHNH || 3223 || 3223 2   NaOHI /2 OH2 3CHI Cl Cl CHCHCHCCH OH OH CHCHCHCCH OH | | 3223 | | 3223 2   176. (e)   OH OH OH CNCCCHHCNCHOCH 3 (A) | | 33 H OH COOHCCH | | 3  177. (b) Aldehyde, which does not have the H atom, gives cannizzaro's reaction on heating with conc. alkali solution (50%) absent atom 56 H CHOHC  atom- 3 | 3 H CH CHCHOCH     absent atom- 3 H CHO OCH  absent atom- 3 | 3 | 3 H CH CH CHOCCH    absent atomH HCHO  Critical Thinking Questions 1. (d) Acetone oxidise by 722 OCrK & conc. 42SOH into carboxylic acid. It is not oxidised by dilute 42SOH . 2. (b) Acetaldehyde react with tollen's reagent while ketone do not react with tollen's reagent. 3. (b)  )hydrateChloral( 2323 .. OHCHOCClOHCHOCCl OH OH CHCCl .3 4. (c) The compound A with formula OHC 63 gives iodoform test, it is propanone forms a compound B having carbon atoms three times, the number of carbon atoms in propanone, it is 2, 6-dimethyl-2, 5-heptadien-4-one. 5. (a) 3223 Butanone2 3 | 23 PPhCHCHCHCH CH OCCHCH   heptene3methyl,3 3322 3 | 23   POPhCHCHHCH CH CCCHCH 6. (a) (B) 23 ][ (A) 223 CHOCHCHOHCHCHCH O    HCl NNHCONHHO H CCHCH 22 | 23 223 NHCONHNCHCHCH  7. (b) Acetophenone is a ketone and does not react with Tollen’s reagent to give silver mirror. 8. (b) (ketoform)Acetone 3 || 3 CH O CCH               formenol 2 | 3 CH OH CCH ⇌ 2 | 3 CH OD CCH  ⇌ O DCHCCH 2 || 3  OH DCHCCH 2 | 2  OD DCHCCH 2 | 2  ⇌ DCH O CDCH 2 || 2  ⇌ 3 || 3 CD O CCD  The enol form of acetone on treatment with OD2 undergoes enolisation, deutration (addition of OD2 ) and dehydration (removal of OH 2 ). The repeated enolisation, deutration and dehydration ultimately gives )B(. 33 COCDCD . 9. (b) Both HClHgZn ),( and OHNHNH ,22 can reduce 3COCH group to 32 CHCH  group, but HCl will also bring about dehydration of alcohol to form alkene. Therefore, appropriate reagent for the conversion is OHNHNH ,22 . 10. (b) 2, 4-hexanedione (a 1, 3-diketone) has the most acidic hydrogen. This is because the carbanion left after the removal of H is resonance stabilised in this case. OH OH CHCH O CCH O CCH 2eHexanedion4,2 32 || 2 || 3     32 |||| 3 CHCH O CHC O CCH   D2O Aldehydes and Ketones 1301 32 |||| 3 CHCH O CHC O CCH   32 ||| 3 CHCH O CCH O CCH   32 ||| 3 CHCH O CCH O CCH   11. (a) Aldols (-hydroxy aldehydes or - hydroxyketones) readily undergo dehydration to form , -unsaturated aldehydes or ketones. 12. (b) 13. (a) Amongst aldehyde & the acid derivatives, acid chloride are the most susceptible to nucleophilic attack due to strong –I effect & weak +R effect of the Cl-atom as a result of which carbonyl carbon has the highest electron deficiency. The actual order is MeCOCl >MeCOOCOMe >MeCOOMe >MeCHO. 14. (ad)   3 / 322 2 CHICHCOCHICH NaOHI COONaCHCH 23 NaOH I CHCH OH CHCH  2 32 | 3 323 CHICOONaCHCH  15. (c) CHP HOH 2 /2    CH 3 CHQ HOH 3 /2    Ketone (non-reducing) and aldehyde (reducing) can be distinguished by Fehling solution. 16. (d)   4 322 3 3 KMnO CHCHCHCHC CH CH 32 3 3 CHHOOCCHOC CH CH  17. (bd) 56 56 3 HCOC COClHC AlCl   2 56 260 56 CO HCOCHCOC C Cu o  18. (d) Aldehyde & ketone are colourless & stable compound 19. (c) It undergoes electrophilic substitution at m- position and also gives iodoform test. 20. (a)   OHCHCCHCH 2 yne1But 23 mtautomeris enol-keto 2 | 23                CH OH CCHCH one2Butan 3 || 23   CH O CCHCH 21. (b) Due to electron withdrawing nature of 2NO group, the partial +ve charge on the carbon atom of the OC  group in p- nitrobenzaldehyde increases and hence becomes more susceptible to nucleophilic attack by CN ion. 22. (b) Cannizzaro reaction is an example of hydride ion )( H transfer reaction. 23. (d) Except 32CONa benzophenone react with rest of option. 24. (d) The alcohol can be converted to aldehyde group by treating with oxidising agent Pyridinium chloro chromate )( 356   ClHCrONHC it is abbreviated as PCC and is called Collin's reagent. This reagent is used in non aqueous solvent like 22ClCH It is a very good reagent because it checks the further oxidation of aldehyde to carboxylic acid while rest oxidising agent oxidise aldehyde into carboxylic acid. 25. (a) ketoximenyl methyl phe 2 or oxime neAcetopheno 3 | 562 3 | 56 CH NOHCHCNOHH CH OCHC OH    eAcetanilid 356 entrearrangem Backmann 42 NHCOCHHC SOH   26. (d) Benzyl alcohol does not have the COCH3 group or OCHCH 23 so it will not give the positive iodoform test. 27. (c) This is perkin reaction O     OHH 2, O OH   H O 2HO  -Hydroxyketone (A) CHO CHO CHO CHO reaction Cannizzaro ularIntramolec 100/    COH o OHCH 2 OHCH 2 COOH COOH COO OHCH 2 CHO OCO     OH 2/H COOH  COOCHHCHOCH C O C O 323 |||| O 3CH OH 3CH OH ⇌ CH3 CHO 1302 Aldehydes and Ketones 28. (b) 29. (c) 30. (a) On complete oxidation the obtained compound shows increament in molecular weight of only 16. It means only one oxygen atom is added here. This condition is fulfilled by only aldehyde which on oxidation gives acid. RCOOHRCHO O  ][ Hence, original compound must be 60 wt.mol. 3 ][ 44 wt.mol. 3 COOHCHCHOCH O  Assertion & Reason 3. (b) It is true that lower aldehyde and ketones are soluble in water but as the molecular mass increases their solubility decreases. On adding Tollen's reagent to a solution of Carbonyl compound if silver mirror is obtained than it is aldehyde. Therefore Tollen's reagent is used for the identification of aldehydes and ketones. Here, assertion and reason both are true but the reason is not the correct explanation of assertion. 4. (a) Carbonyl compounds having -hydrogen atom condenses to produce aldol in presence of alkali.   NaOH CHOHCHH O CCH dil. 2 || 3 deAcetaldehy CHOCH OH CHCH Aldol 2 | 3  5. (d) Acetylene, on treatment with alkaline 4KMnO is oxidised to produce oxalic acid. acidOxalic | 4 alk. ][4 ||| COOH COOH Acetylene CH CH KMnO O  Therefore, both assertion and reason are false. 6. (b) Acetophenone and benzophenone can be distinguish by iodoform test. Both are carbonyl compounds. Assertion and reason both are true but reason is not the correct explanation of assertion. 7. (c) CHOCH CH CH  3 3 Isobutanol has -hydrogen atom. Acetaldehyde, acetone and methyl ketones having COCH 3 group undergo haloform reaction. The halogen atoms of the methyl group are first replaced by hydrogen atoms. This reaction is used as a test of COCH3 – 23 |||| HCOCH C O C O  H O CMe  || OH NCHH 2 32    O 3CHN    4LiAlH 3CHN  COOHCHCHCOOHCH 233  2232|||| 3 OHCHCH O C O CCH    3 323 O CHCHCCCH 32 || 3 CHCH O C O CCH  O OH 2 OHCHCHOCH C O C O 23 |||| Me    COOHCH OCHCHOCH C O C O 3 23 |||| Me COOCHCOOHCHCHMe 3 OH H 2      OH CHCHCHOCH C O C O 2 33 ||||