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Aldehydes, Ketones And Carboxylic Acids Class 12th Chemistry Part Ii CBSE Solution

Class 12th Chemistry Part Ii CBSE Solution
Intext Questions Pg-353
  1. α-Methoxypropionaldehyde Write the structures of the following compounds.…
  2. 3-Hydroxybutanal Write the structures of the following compounds.…
  3. 2-Hydroxycyclopentane carbaldehyde Write the structures of the following compounds.…
  4. 4-Oxopentanal Write the structures of the following compounds.
  5. Di-sec. butyl ketone Write the structures of the following compounds.…
  6. 4-Fluoroacetophenone Write the structures of the following compounds.…
Intext Questions Pg-356
  1. Write the structures of products of the following reactions;(i) (ii) (iii) (iv)…
Intext Questions Pg-358
  1. Arrange the following compounds in increasing order of their boiling points.CH3CHO,…
Intext Questions Pg-365
  1. Ethanal, Propanal, Propanone, Butanone. Hint: Consider steric effect and electronic…
  2. Benzaldehyde, p-Tolualdehyde, p-Nitrobenzaldehyde, Acetophenone. Hint: Consider steric…
  3. Predict the products of the following reactions: (i) (ii) (iii) (iv)…
Intext Questions Pg-367
  1. Ph CH2CH2COOH Give the IUPAC names of the following compounds:
  2. (CH3)2C = CHCOOH Give the IUPAC names of the following compounds:…
  3. Give the IUPAC names of the following compounds:
  4. Give the IUPAC names of the following compounds:
Intext Questions Pg-370
  1. Ethylbenzene Show how each of the following compounds can be converted to benzoic acid.…
  2. Acetophenone Show how each of the following compounds can be converted to benzoic acid.…
  3. Bromobenzene Show how each of the following compounds can be converted to benzoic acid.…
  4. Phenylethene (Styrene) Show how each of the following compounds can be converted to…
Intext Questions Pg-376
  1. CH3CO2H or CH2FCO2H Which acid of each pair shown here would you expect to be stronger?…
  2. CH2FCO2H or CH2ClCO2H Which acid of each pair shown here would you expect to be stronger?…
  3. CH2FCH2CH2CO2H or CH3CHFCH2CO2H Which acid of each pair shown here would you expect to be…
  4. Which acid of each pair shown here would you expect to be stronger?…
Exercises
  1. Cyanohydrins What is meant by the following terms? Give an example of the reaction in each…
  2. Acetal What is meant by the following terms? Give an example of the reaction in each case.…
  3. Semicarbazone What is meant by the following terms? Give an example of the reaction in…
  4. Aldol What is meant by the following terms? Give an example of the reaction in each case.…
  5. Hemiacetal What is meant by the following terms? Give an example of the reaction in each…
  6. Oxime What is meant by the following terms? Give an example of the reaction in each case.…
  7. Ketal What is meant by the following terms? Give an example of the reaction in each case.…
  8. Imine What is meant by the following terms? Give an example of the reaction in each case.…
  9. 2,4-DNP-derivative What is meant by the following terms? Give an example of the reaction…
  10. Schiff’s base What is meant by the following terms? Give an example of the reaction in…
  11. CH3CH(CH3)CH2CH2CHO Name the following compounds according to IUPAC system of…
  12. CH3CH2COCH(C2H5)CH2CH2Cl Name the following compounds according to IUPAC system of…
  13. CH3CH=CHCHO Name the following compounds according to IUPAC system of nomenclature:…
  14. CH3COCH2COCH3 Name the following compounds according to IUPAC system of nomenclature:…
  15. CH3CH(CH3)CH2C(CH3)2COCH3 Name the following compounds according to IUPAC system of…
  16. (CH3)3CCH2COOH Name the following compounds according to IUPAC system of nomenclature:…
  17. OHCC6H4CHO-p Name the following compounds according to IUPAC system of nomenclature:…
  18. 3-Methylbutanal Draw the structures of the following compounds.
  19. p-Nitropropiophenone Draw the structures of the following compounds.…
  20. p-Methylbenzaldehyde Draw the structures of the following compounds.…
  21. 4-Methylpent-3-en-2-one Draw the structures of the following compounds.…
  22. 4-Chloropentan-2-one Draw the structures of the following compounds.…
  23. 3-Bromo-4-phenylpentanoic acid Draw the structures of the following compounds.…
  24. p,p’-Dihydroxybenzophenone Draw the structures of the following compounds.…
  25. Hex-2-en-4-ynoic acid Draw the structures of the following compounds.…
  26. CH3CO(CH2)4CH3 Write the IUPAC names of the following ketones and aldehydes. Wherever…
  27. CH3CH2CHBrCH2CH(CH3)CHO Write the IUPAC names of the following ketones and aldehydes.…
  28. CH3(CH2)5CHO Write the IUPAC names of the following ketones and aldehydes. Wherever…
  29. Ph-CH=CH-CHO Write the IUPAC names of the following ketones and aldehydes. Wherever…
  30. Write the IUPAC names of the following ketones and aldehydes. Wherever possible, give…
  31. PhCOPh Write the IUPAC names of the following ketones and aldehydes. Wherever possible,…
  32. The 2, 4-dinitrophenylhydrazone of benzaldehyde Draw structures of the following…
  33. Cyclopropanone oxime Draw structures of the following derivatives.…
  34. Acetaldehydedimethylacetal Draw structures of the following derivatives.…
  35. The semicarbazone of cyclobutanone Draw structures of the following derivatives.…
  36. The ethylene ketal of hexan-3-one Draw structures of the following derivatives.…
  37. The methyl hemiacetal of formaldehyde Draw structures of the following derivatives.…
  38. PhMgBr and then H3O+ Predict the products formed when cyclohexanecarbaldehyde reacts with…
  39. Tollens’ reagent Predict the products formed when cyclohexanecarbaldehyde reacts with…
  40. Semicarbazide and weak acid Predict the products formed when cyclohexanecarbaldehyde…
  41. Excess ethanol and acid Predict the products formed when cyclohexanecarbaldehyde reacts…
  42. Zinc amalgam and dilute hydrochloric acid Predict the products formed when…
  43. Which of the following compounds would undergo aldol condensation, which the Cannizzaro…
  44. Butane-1,3-diol How will you convert ethanal into the following compounds?…
  45. But-2-enal How will you convert ethanal into the following compounds?…
  46. But-2-enoic acid How will you convert ethanal into the following compounds?…
  47. Write structural formulas and names of four possible aldol condensation products from…
  48. An organic compound with the molecular formula C9H10O forms 2,4-DNP derivative, reduces…
  49. An organic compound (A) (molecular formula C8H16O2) was hydrolysed with dilute sulphuric…
  50. Acetaldehyde, Acetone, Di-tert-butyl ketone, Methyl tert-butyl ketone (reactivity towards…
  51. CH3CH2CH(Br)COOH, CH3CH(Br)CH2COOH, (CH3)2CHCOOH, CH3CH2CH2COOH (acid strength) Arrange…
  52. Benzoic acid, 4-Nitrobenzoic acid, 3,4-Dinitrobenzoic acid, 4-Methoxybenzoic acid (acid…
  53. Propanal and Propanone Give simple chemical tests to distinguish between the following…
  54. Acetophenone and Benzophenone Give simple chemical tests to distinguish between the…
  55. Phenol and Benzoic acid Give simple chemical tests to distinguish between the following…
  56. Benzoic acid and Ethyl benzoate Give simple chemical tests to distinguish between the…
  57. Pentan-2-one and Pentan-3-one Give simple chemical tests to distinguish between the…
  58. Benzaldehyde and Acetophenone Give simple chemical tests to distinguish between the…
  59. Ethanal and Propanal Give simple chemical tests to distinguish between the following pairs…
  60. Methyl benzoate How will you prepare the following compounds from benzene? You may use any…
  61. m-Nitrobenzoic acid How will you prepare the following compounds from benzene? You may use…
  62. p-Nitrobenzoic acid How will you prepare the following compounds from benzene? You may use…
  63. Phenylacetic acid How will you prepare the following compounds from benzene? You may use…
  64. p-Nitrobenzaldehyde. How will you prepare the following compounds from benzene? You may…
  65. Propanone to Propene How will you bring about the following conversions in not more than…
  66. Benzoic acid to Benzaldehyde How will you bring about the following conversions in not…
  67. Ethanol to 3-Hydroxybutanal How will you bring about the following conversions in not more…
  68. Benzene to m-Nitroacetophenone How will you bring about the following conversions in not…
  69. Benzaldehyde to Benzophenone How will you bring about the following conversions in not…
  70. Bromobenzene to 1-Phenylethanol How will you bring about the following conversions in not…
  71. Benzaldehyde to 3-Phenylpropan-1-ol How will you bring about the following conversions in…
  72. Benazaldehyde to α-Hydroxyphenylacetic acid How will you bring about the following…
  73. Benzoic acid to m- Nitrobenzyl alcohol How will you bring about the following conversions…
  74. Acetylation- Describe the following:
  75. Cannizzaro reaction Describe the following:
  76. Cross aldol condensation Describe the following:
  77. Decarboxylation Describe the following:
  78. Complete each synthesis by giving missing starting material, reagent or products…
  79. Complete each synthesis by giving missing starting material, reagent or products…
  80. Complete each synthesis by giving missing starting material, reagent or products…
  81. Complete each synthesis by giving missing starting material, reagent or products…
  82. Complete each synthesis by giving missing starting material, reagent or products…
  83. Complete each synthesis by giving missing starting material, reagent or products…
  84. Complete each synthesis by giving missing starting material, reagent or products…
  85. CH3COCH2COOC2H5 Complete each synthesis by giving missing starting material, reagent or…
  86. Complete each synthesis by giving missing starting material, reagent or products…
  87. Complete each synthesis by giving missing starting material, reagent or products…
  88. Complete each synthesis by giving missing starting material, reagent or products…
  89. Cyclohexanone forms cyanohydrin in good yield but 2,2,6-trimethylcyclohexanone does not.…
  90. There are two -NH2 groups in semicarbazide. However, only one is involved in the formation…
  91. During the preparation of esters from a carboxylic acid and an alcohol in the presence of…
  92. An organic compound contains 69.77% carbon, 11.63% hydrogen and rest oxygen. The molecular…
  93. Although phenoxide ion has more number of resonating structures than carboxylate ion, the…
Intext Questions Pg-353
Question 1.

Write the structures of the following compounds.

α-Methoxypropionaldehyde


Answer:

The compound contains ether group and an aldehydic functional group with the longest chain having 3 carbon atoms. α


means the position of the carbon atom attached to attached to the carbon atom of the functional group, in this case, it is an aldehyde functional group.




Question 2.

Write the structures of the following compounds.

3-Hydroxybutanal


Answer:

The compound contains an alcoholic group and an aldehydic functional group with the longest chain having 4 carbon atoms. The numbering of the chain starts from a carbon atom of aldehyde group.




Question 3.

Write the structures of the following compounds.

2-Hydroxycyclopentane carbaldehyde


Answer:

The compound contains alcoholic group and an aldehydic functional group with the longest chain having 5 carbon atoms which are cyclic in nature. The numbering of the chain starts from a carbon atom of aldehyde group attached to the cyclopentane ring.




Question 4.

Write the structures of the following compounds.

4-Oxopentanal


Answer:

The compound contains ketone group and an aldehydic functional group with the longest chain having 5 carbon atoms. The numbering of the chain starts from a carbon atom of aldehyde group.




Question 5.

Write the structures of the following compounds.

Di-sec. butyl ketone


Answer:

The compound contains ketone functional group with the longest chain having 8(butyl is used because there is two similar butyl group attached to the carbonyl carbon of ketone group) carbon atoms.




Question 6.

Write the structures of the following compounds.

4-Fluoroacetophenone


Answer:

The compound contains a fluorine atom and a ketone functional group with the longest chain which is a derivative of a phenyl group and an acetyl substituent.




Intext Questions Pg-356
Question 1.

Write the structures of products of the following reactions;

(i) 

(ii) 

(iii) 

(iv) 


Answer:

(i)


(ii)



(iii)



(iv)




Intext Questions Pg-358
Question 1.

Arrange the following compounds in increasing order of their boiling points.

CH3CHO, CH3CH2OH, CH3OCH3, CH3CH2CH3


Answer:

The molecular masses of the given compounds are in the range of 44-66 g/mol. The second molecule, CH3CH2OH contains OH alcoholic group due to which it undergoes extensive H bonding with each other, leading to the association of the molecules. Therefore it has a highest boiling point. In the molecule CH3CHO , there is strong intermolecular dipole-dipole attraction due to presence of -CHO aldehydic group( as H will have partial positive charge and oxygen will have partial negative charge , so there will attraction between molecules),which is weak in case of CH3OCH3 as both CH3 groups have +I effect which results in decrease in electron affinity for the oxygen attached to it( with no partially positive H atom). And in CH3CH2CH3 there are only weak van der Waals forces of attraction. So the compounds in increasing order of their boiling point are:

CH3CH2CH3<CH3OCH3<CH3CHO<CH3CH2OH.



Intext Questions Pg-365
Question 1.

Arrange the following compounds in increasing order of their reactivity in nucleophilic addition reactions.

Ethanal, Propanal, Propanone, Butanone.

Hint: Consider steric effect and electronic effect.


Answer:

The +I effect increases in the order as:


Ethanal<Propanal<Propanone<Butanone.



Therefore the electron density of the carbonyl carbon increases as the +I effect due to the alkyl group increases. As a result, the chances of attack by a nucleophile (which are rich in electron and carries a negative charge, not necessary usually have a lone pair of an electron) decreases because the carbonyl carbon has electron density on it. Hence the increasing order of the reactivities of given compounds in nucleophilic addition reaction is:


Ethanal > Propanal> Propanone > Butanone.



Question 2.

Arrange the following compounds in increasing order of their reactivity in nucleophilic addition reactions.

Benzaldehyde, p-Tolualdehyde, p-Nitrobenzaldehyde, Acetophenone.

Hint: Consider steric effect and electronic effect.


Answer:


The +I effect is more in ketone than in aldehyde because in ketone there are 2 alkyl groups contributing in the +I effect whereas in aldehydes there is only one alkyl group. Hence, acetophenone(being ketone group attached to it) is the least reactive in nucleophilic addition reactions. Among aldehydes, the +I effect is the highest in p-tolualdehyde because of the presence of the electron-donating –CH3 group(which increase the electron density on the carbonyl carbon via resonance through the benzene ring) and the lowest in p-nitrobenzaldehyde because of the presence of the electron-withdrawing –NO2 group(which decreases the electron density on the carbonyl carbon via resonance through the benzene ring). Hence, the increasing order of the reactivities of the given compounds is:


Acetophenone<p-tolualdehyde<Benzaldehyde<p-Nitrobenzaldehyde



Question 3.

Predict the products of the following reactions:

(i) 

(ii) 

(iii) 

(iv) 


Answer:

(i)


Cyclopentanone reacts with hydroxylamine to give cyclopentanone oxime. As you can see the cyclopentanone has ketone functional group with oxygen attached to carbonyl carbon and the hydroxylamine has two H atoms attached to N. And hence in the product this O and two H atoms are removed and form a water molecule.


(ii)



(iii)



(iv)



Trick: remember if any aldehyde or ketone bearing compound reacts with primary or secondary amine then for finding the product formed simply remove the oxygen atom from the aldehyde or ketone functional group and two H atoms attached to N in amines and add a double bond between C and N.



Intext Questions Pg-367
Question 1.

Give the IUPAC names of the following compounds:

Ph CH2CH2COOH


Answer:

The compound contains carboxylic acid as the functional group and Ph means a phenyl group. The longest chain contains 3 carbon atom with phenyl group of carbon 3 so the IUPAC name of the compound is 3-phenylpropanoic acid.



Question 2.

Give the IUPAC names of the following compounds:

(CH3)2C = CHCOOH


Answer:

The longest chain contains 4 carbon atom with a methyl group as a substituent and a carboxylic acid as a functional group. The no. Of the chain starts from the carbon atom of the –COOH group with double bond on carbon 2 so the IUPAC name of the compound is 3-Methylbut-2-enoic acid.



Question 3.

Give the IUPAC names of the following compounds:



Answer:

The longest chain has 5 carbon atom(all are saturated) which are cyclic with the carboxylic group attached and a methyl group as a substituent. The no. Of the chain starts from the carbon atom of the –COOH group so the IUPAC name of the compound is 2-Methylcyclopentane carboxylic acid.



Question 4.

Give the IUPAC names of the following compounds:



Answer:

The longest chain is derivative of benzene with the carboxylic group attached and 3 nitro groups. The no. Of the chain starts from the carbon atom of the –COOH group so the IUPAC name of the compound is 2,4,6-Trinitrobenzoic acid.



Intext Questions Pg-370
Question 1.

Show how each of the following compounds can be converted to benzoic acid.

Ethylbenzene


Answer:


In the presence of nascent oxygen i.e. [O] along with KMnO4/ KOH(it is a very strong oxidizing agent which oxidizes the whole alkyl group to carboxylic salt) followed by hydrolysis leads to the formation of benzoic acid. Carbon dioxide and water are formed as byproducts.



Question 2.

Show how each of the following compounds can be converted to benzoic acid.

Acetophenone


Answer:

The oxidation with alcoholic KMNO4 followed by hydrolysis leads to the formation of benzoic acid. The reaction is given below:




Question 3.

Show how each of the following compounds can be converted to benzoic acid.

Bromobenzene


Answer:

Bromobenzene is first reacted with magnesium in presence of dry ether to give an intermediate which on reaction with solid carbon dioxide followed by hydrolysis leads to the formation of benzoic acid.




Question 4.

Show how each of the following compounds can be converted to benzoic acid.

Phenylethene (Styrene)


Answer:

Here the oxidation of styrene with alcoholic KMNO4 is followed by hydrolysis leads to the formation of benzoic acid.




Intext Questions Pg-376
Question 1.

Which acid of each pair shown here would you expect to be stronger?

CH3CO2H or CH2FCO2H


Answer:

The +I effect of –CH3 group increases the electron density on the O-H bond. Therefore, the release of proton becomes difficult. On the other hand, the -I effect of F decreases the electron density on the O-H bond. Therefore, the proton can be released easily. Hence, CH2FCO2H is a stronger acid than CH3CO2H.


NOTE:A strong acid is an acid which dissociates completely releasing almost all of its protons in the solution.




Question 2.

Which acid of each pair shown here would you expect to be stronger?

CH2FCO2H or CH2ClCO2H


Answer:

F has stronger -I effect than Cl(as fluorine is more electronegative than chlorine). Therefore, CH2FCO2H can release proton more easily than CH2ClCO2H. Hence, CH2FCO2H is a stronger acid than CH2ClCO2H.




Question 3.

Which acid of each pair shown here would you expect to be stronger?

CH2FCH2CH2CO2H or CH3CHFCH2CO2H


Answer:

Inductive effect decreases with increase in distance(the more will be the distance of the inductive group from the carboxylic group less will be its effect of polarisability). Hence, the -I effect of F in CH3CHFCH2CO2H is more than it is in CH2FCH2CH2CO2H . Hence, CH3CHFCH2CO2H is a stronger acid than CH2FCH2CH2CO2H .




Question 4.

Which acid of each pair shown here would you expect to be stronger?



Answer:

Due to the -I effect of F(being electronegative), it is easier to release proton in the case of compound (A). However, in the case of compound (B), the release of the proton is difficult due to the +I effect of –CH3 i.e. methyl group. Hence, (A) is a stronger acid than (B).




Exercises
Question 1.

What is meant by the following terms? Give an example of the reaction in each case.

Cyanohydrins


Answer:

Cyanohydrin:


Cyanohydrins are those organic compounds having the formula RR“2C(OH)CN, wherever R and R“2 can be alkyl or aryl groups.


Aldehydes and ketones react with compound (KCN) within the presence of excess cyanide (NaCN) as a catalyst to field organic compound.



Question 2.

What is meant by the following terms? Give an example of the reaction in each case.

Acetal


Answer:

Acetal:


Acetals are gem - dialkoxy alkanes within which 2 alkoxy teams groups attached to the terminal atom. One bond is connected to associate degree alkyl whereas the opposite is connected to the hydrogen atom.


When aldehydes are treated with 2 equivalents of a monohydric alcohol within the presence of dry HCl gas, hemiacetals are produced which are further reacted with one more molecule to alcohol to yield acetal as shown below:




Question 3.

What is meant by the following terms? Give an example of the reaction in each case.

Semicarbazone


Answer:

Semicarbarbazone:


Semicarbazones are the derivatives of organic compounds produced by the condensation reaction between a ketone or aldehyde and semicarbazide.


Semicarbazones square measure helpful for identification and characterization of aldehydes and ketones.




Question 4.

What is meant by the following terms? Give an example of the reaction in each case.

Aldol


Answer:

Aldol:


An aldol is a β-hydroxy organic compound. It's produced by the by the condensation reaction of 2 molecules of an equivalent or one molecule every of 2 totally different aldehydes or ketones within the presence of a base.


The reaction is shown as below:




Question 5.

What is meant by the following terms? Give an example of the reaction in each case.

Hemiacetal


Answer:

Hemiacetal:


Hemiacetals are α-alkoxyalcohols.


Aldehyde reacts with one molecule of a monohydric alcohol in the presence of dry HCl gas to from aloxy alcohol, known as hemiacetal.


The following reaction shows the formation of hemiacetal:




Question 6.

What is meant by the following terms? Give an example of the reaction in each case.

Oxime


Answer:

Oxime:


Oximes are a category of organic compounds having the final formula RR“2CNOH, where R is an associate organic aspect chain associated R“2 is either H or an organic aspect chain. If R“2 is H, then it's called aldoxime associated if R“2 is an organic aspect chain, it's called ketoxime.


On treatment with hydroxylamine in a very decrepit acidic medium, aldehydes or ketones kind oximes.




Question 7.

What is meant by the following terms? Give an example of the reaction in each case.

Ketal


Answer:

Ketal:


Ketals area gem – dialkoxyalkanes in which two which 2 alkoxy teams are attached inside the chain. The opposite 2 bonds of the atom are unit connected to 2 alkyl groups.


The general structure of ketal is shown as below:



Ketones react with glycol within the presence of dry HCl gas to grant a cyclic product referred to as glycol ketals.




Question 8.

What is meant by the following terms? Give an example of the reaction in each case.

Imine


Answer:

Imine:


An organic compound which contains a carbon–nitrogen double bond.


The structure of imine is shown as below:



Imines are produced when aldehydes and ketones react with ammonia Gas.




Question 9.

What is meant by the following terms? Give an example of the reaction in each case.

2,4-DNP-derivative


Answer:

2, 4 - DNP - derivative:


2, 4 - DNP - derivative is a substituted hydrazine,


The molecular formula for 2,4-DNP–derivative is C6H3(NO2)2NHNH2.


The other name is Dinitrophenylhydrazine is the chemical compound. Dinitrophenylhydrazine is a red to orange solid. It is a


aldehydes or ketones react with 2, 4 - dinitrophenylhydrazine to form yellow, orange, or red coloured derivatives named as 2,4 dinitrogenphenylhydrazones. These are also known as 2,4-DNP derivative.




Question 10.

What is meant by the following terms? Give an example of the reaction in each case.

Schiff’s base


Answer:

Schiff's base:


Aldehydes and ketones on react with primary amines in the presence of trace of an acid yields a Schiff's base.




Question 11.

Name the following compounds according to IUPAC system of nomenclature:

CH3CH(CH3)CH2CH2CHO


Answer:


4-methylpentanal



Question 12.

Name the following compounds according to IUPAC system of nomenclature:

CH3CH2COCH(C2H5)CH2CH2Cl


Answer:



Question 13.

Name the following compounds according to IUPAC system of nomenclature:

CH3CH=CHCHO


Answer:


But-2-en-1-al



Question 14.

Name the following compounds according to IUPAC system of nomenclature:

CH3COCH2COCH3


Answer:


Pentane-2,4-dione



Question 15.

Name the following compounds according to IUPAC system of nomenclature:

CH3CH(CH3)CH2C(CH3)2COCH3


Answer:


3,3,5-Trimethylhexan-2-one



Question 16.

Name the following compounds according to IUPAC system of nomenclature:

(CH3)3CCH2COOH


Answer:


3,3-Dimethylbutanoic acid



Question 17.

Name the following compounds according to IUPAC system of nomenclature:

OHCC6H4CHO-p


Answer:


Benzene-1,4-dicarbaldehyde



Question 18.

Draw the structures of the following compounds.

3-Methylbutanal


Answer:

3-Methylbutanal-




Question 19.

Draw the structures of the following compounds.

p-Nitropropiophenone


Answer:

p-Nitropropiophenone-




Question 20.

Draw the structures of the following compounds.

p-Methylbenzaldehyde


Answer:

p-Methylbenzaldehyde-




Question 21.

Draw the structures of the following compounds.

4-Methylpent-3-en-2-one


Answer:

4-Methylpent-3-en-2-one-




Question 22.

Draw the structures of the following compounds.

4-Chloropentan-2-one


Answer:

4-Chloropentan-2-one-




Question 23.

Draw the structures of the following compounds.

3-Bromo-4-phenylpentanoic acid


Answer:

3-Bromo-4-phenylpentanoic acid-




Question 24.

Draw the structures of the following compounds.

p,p’-Dihydroxybenzophenone


Answer:

p,p’-Dihydroxybenzophenone-




Question 25.

Draw the structures of the following compounds.

Hex-2-en-4-ynoic acid


Answer:

Hex-2-en-4-ynoic acid-




Question 26.

Write the IUPAC names of the following ketones and aldehydes. Wherever possible, give also common names.

CH3CO(CH2)4CH3


Answer:

CH3CO(CH2)4CH3



IUPAC name: Heptan-2-one


Common name: Methyl n-propyl ketone



Question 27.

Write the IUPAC names of the following ketones and aldehydes. Wherever possible, give also common names.

CH3CH2CHBrCH2CH(CH3)CHO


Answer:

CH3CH2CHBrCH2CH(CH3)CHO



IUPAC name: 4-Bromo-2-methylhaxanal


Common name: (γ-Bromo-α-methyl-caproaldehyde)



Question 28.

Write the IUPAC names of the following ketones and aldehydes. Wherever possible, give also common names.

CH3(CH2)5CHO


Answer:

CH3(CH2)5CHO



IUPAC name: Heptanal



Question 29.

Write the IUPAC names of the following ketones and aldehydes. Wherever possible, give also common names.

Ph-CH=CH-CHO


Answer:

Ph-CH=CH-CHO



IUPAC name: 3-phenylprop-2-enal


Common name: β-Pheynolacrolein



Question 30.

Write the IUPAC names of the following ketones and aldehydes. Wherever possible, give also common names.



Answer:


IUPAC name: Cyclopentanecarbaldehyde



Question 31.

Write the IUPAC names of the following ketones and aldehydes. Wherever possible, give also common names.

PhCOPh


Answer:

PhCOPh



IUPAC name: Diphenylmethanone


Common name: Benzophenone



Question 32.

Draw structures of the following derivatives.

The 2, 4-dinitrophenylhydrazone of benzaldehyde


Answer:

The 2, 4-dinitrophenylhydrazone of benzaldehyde




Question 33.

Draw structures of the following derivatives.

Cyclopropanone oxime


Answer:

Cyclopropanone oxime




Question 34.

Draw structures of the following derivatives.

Acetaldehydedimethylacetal


Answer:

Acetaldehyde dimethylacetal




Question 35.

Draw structures of the following derivatives.

The semicarbazone of cyclobutanone


Answer:

The semicarbazone of cyclobutanone




Question 36.

Draw structures of the following derivatives.

The ethylene ketal of hexan-3-one


Answer:

The ethylene ketal of hexan-3-one




Question 37.

Draw structures of the following derivatives.

The methyl hemiacetal of formaldehyde


Answer:

The methyl hemiacetal of formaldehyde




Question 38.

Predict the products formed when cyclohexanecarbaldehyde reacts with following reagents.

PhMgBr and then H3O+


Answer:

PhMgBr and then H3O+




Question 39.

Predict the products formed when cyclohexanecarbaldehyde reacts with following reagents.

Tollens’ reagent


Answer:

Tollens’ reagent




Question 40.

Predict the products formed when cyclohexanecarbaldehyde reacts with following reagents.

Semicarbazide and weak acid


Answer:

Semicarbazide and weak acid




Question 41.

Predict the products formed when cyclohexanecarbaldehyde reacts with following reagents.

Excess ethanol and acid


Answer:

Excess ethanol and acid




Question 42.

Predict the products formed when cyclohexanecarbaldehyde reacts with following reagents.

Zinc amalgam and dilute hydrochloric acid


Answer:

Zinc amalgam and dilute hydrochloric acid




Question 43.

Which of the following compounds would undergo aldol condensation, which the Cannizzaro reaction and which neither? Write the structures of the expected products of aldol condensation and Cannizzaro reaction.

(i) Methanal

(ii) 2-Methylpentanal

(iii) Benzaldehyde

(iv) Benzophenone

(v) Cyclohexanone

(vi) 1-Phenylpropanone

(vii) Phenylacetaldehyde

(viii) Butan-1-ol

(ix) 2,2-Dimethylbutanal


Answer:

Aldehydes and ketones having at least one α-hydrogen undergo aldol condensation. The compounds


(ii) 2-methylpentanal


(v)cyclohexanone


(vi) 1-phenylpropanone


(vii) phenylacetaldehyde


contain one or more α-hydrogen atoms. Therefore, these undergo aldol condensation.


Aldehydes having no α-hydrogen atoms undergo Cannizzaro reactions. The compounds


(i) Methanal


(iii)Benzaldehyde


(ix) 2, 2-dimethylbutanal


do not have any α-hydrogen. Therefore, these undergo cannizzaro reactions.


Compound (iv) Benzophenone is a ketone having no α-hydrogen atom and compound (viii) Butan-1-ol is an alcohol. Hence, these compounds do not undergo either aldol condensation or cannizzaro reactions.


Structures of the expected products of aldol condensation and Cannizzaro reaction-


Aldol condensation-


(ii) 2-methylpentanal-



(v)cyclohexanone-