organic chemistry important question |class 12|

chapterwise important questions of chemistry |class12|organic chemistry|NEB

FROM HALOALKANE

1. What happens when a haloalkane is heated with an alcoholic solution of potassium hydroxide?
2. What happens when a primary haloalkane is treated with a strong base like sodium ethoxide?
3. What happens when a haloalkane is treated with a strong nucleophile like hydroxide ion?
4. What happens when a haloalkane is treated with a weak nucleophile like water?
5. What happens when a haloalkane is treated with silver nitrate in ethanol?
6. What happens when a haloalkane is treated with sodium iodide in acetone?
7. What happens when a haloalkane is treated with a reducing agent like zinc and hydrochloric acid?
8. What happens when a haloalkane is treated with a Grignard reagent?
9. What happens when a haloalkane is treated with a Lewis acid like aluminum chloride?
10. What happens when a haloalkane is treated with a strong reducing agent like lithium aluminum hydride?
11. What happens when a haloalkane is treated with sodium metal in dry ether?
12. What happens when a haloalkane is treated with a tertiary amine like triethylamine?
13. What happens when a haloalkane is treated with a base like sodium bicarbonate?
14. What happens when a haloalkane is treated with a dehydrohalogenating agent like potassium tert-butoxide?
15. What happens when a haloalkane is treated with a strong acid like sulfuric acid?
16. What happens when a haloalkane is treated with a metal like magnesium?
17. What happens when a haloalkane is treated with a reducing agent like sodium borohydride?
18. What happens when a haloalkane is treated with a nucleophilic substitution reagent like ammonia?
19. What happens when a haloalkane is treated with a reagent that induces a free radical substitution reaction?
20. What happens when a haloalkane is treated with a catalytic amount of palladium in the presence of hydrogen gas?
21. What is the structure of chloroform?
22. How is chloroform prepared in the laboratory?
23. What is the mechanism of the preparation of chloroform by the chlorination of methane?
24. How does chloroform react with water, and what products are formed?
25. What happens when chloroform is treated with a reducing agent like zinc dust?

HALOARENES

1. What happens when bromobenzene is treated with sodium in liquid ammonia?
2. What happens when chlorobenzene is treated with a strong base like sodium hydroxide?
3. What happens when chlorobenzene is treated with chlorine in the presence of a catalyst?
4. What happens when chlorobenzene is treated with nitric acid in the presence of a catalyst?
5. What happens when phenol is treated with bromine water?
6. What happens when aniline is treated with bromine water?
7. What happens when benzene is treated with a mixture of nitric acid and sulfuric acid?
8. What happens when halobenzenes are treated with alkali metals in the presence of dry ether?
9. What happens when halobenzenes are treated with aqueous sodium hydroxide solution?
10. What happens when halobenzenes are treated with metallic sodium in the presence of dry ether?
11. Describe the process of the preparation of DDT from chlorobenzene. What are the reagents and conditions used in each step of the reaction?
12. What are the advantages and disadvantages of using chlorobenzene as a starting material for the synthesis of DDT? How can we overcome the challenges associated with this approach?

ALCOHOLS

1. What happens when a primary alcohol is treated with sodium metal in the presence of dry ether? Describe the reaction and the products formed.
2. What happens when a secondary alcohol is oxidized with potassium permanganate in acidic medium? Describe the reaction and the products formed.
3. What happens when a tertiary alcohol is treated with hydrochloric acid in the presence of zinc chloride? Describe the reaction and the products formed.
4. What is Victor Meyer's method for the determination of the molecular weight of a volatile liquid? How does it work, and what are the key steps involved in the experiment?
5. How can Victor Meyer's method be used to determine the molecular weight of a low-boiling alcohol? What are the advantages and limitations of this method compared to other methods of molecular weight determination?
6. What are some of the factors that can affect the accuracy and precision of the Victor Meyer's method? How can we control for these factors to obtain reliable results?
7. What are the different methods for the preparation of alcohols? Describe the reaction mechanism for each method.
8. What happens when primary alcohols are treated with oxidizing agents like potassium permanganate or potassium dichromate? What products are formed?
9. What happens when secondary alcohols are treated with oxidizing agents like potassium permanganate or potassium dichromate? What products are formed?
10. What happens when tertiary alcohols are treated with oxidizing agents like potassium permanganate or potassium dichromate? Why do tertiary alcohols not undergo oxidation?
11. What happens when alcohols are treated with acidified potassium dichromate? What products are formed?
12. What happens when alcohols are treated with Lucas reagent (a mixture of zinc chloride and hydrochloric acid)? What products are formed?
13. What happens when alcohols are treated with phosphorus tribromide (PBr3)? What products are formed?
14. What happens when alcohols are treated with phosphorus pentoxide (P2O5)? What products are formed?
15. What is the Victor Meyer's method for the determination of molecular weight of a volatile liquid? How does this method work?
16. What happens when primary alcohols are treated with thionyl chloride (SOCl2)? What products are formed?

PHENOLS

1. What happens when phenol is treated with bromine water?
2. What happens when phenol is treated with nitric acid?
3. What happens when phenol is treated with dilute sodium hydroxide?
4. What happens when phenol is treated with acetic anhydride in the presence of a catalyst?
5. What happens when phenol is treated with ferric chloride?
6. What happens when phenol is treated with concentrated sulfuric acid?
7. Describe the different methods for the preparation of phenols, including the Dow process, the Raschig process, and the cumene process. Compare and contrast these methods in terms of their efficiency, cost, and environmental impact.
8. What are the different types of reactions that phenols undergo, such as electrophilic aromatic substitution, nucleophilic substitution, and oxidation? Give examples of each type of reaction and describe the reaction mechanism in detail.
9. Discuss the properties of phenols that make them useful in various applications, such as in the production of plastics, pharmaceuticals, and cosmetics. What are some of the advantages and disadvantages of using phenols in these applications?
10. Phenols are often used as disinfectants and antiseptics. Describe the mechanism by which phenols kill bacteria and viruses, and compare the effectiveness of phenols with other types of disinfectants, such as alcohols and quaternary ammonium compounds.
11. Explain the role of phenols in environmental pollution, particularly in the formation of photochemical smog and the degradation of natural organic matter. What are some of the measures that can be taken to reduce the impact of phenols on the environment?

ETHERS

1. What is the Williamson synthesis of ethers? Describe the reaction mechanism for the synthesis of an ether using an alkoxide and an alkyl halide.
2. What are the factors that determine the efficiency of the Williamson synthesis of ethers? How can we optimize the reaction conditions to increase the yield of the desired ether product?

ALDEHYDE AND KETONES

1. How can you convert an aldehyde to a primary alcohol? Describe the reaction mechanism involved in this conversion.
2. How can you convert a ketone to a secondary alcohol? Describe the reaction mechanism involved in this conversion.
3. How can you convert an aldehyde to a carboxylic acid? Describe the reaction mechanism involved in this conversion.
4. How can you convert a ketone to an ester? Describe the reaction mechanism involved in this conversion.
5. How can you convert an aldehyde to a nitrile? Describe the reaction mechanism involved in this conversion.
6. Describe the oxidation of primary alcohols to aldehydes using different oxidizing agents, such as pyridinium chlorochromate (PCC), chromic acid, and potassium permanganate. Compare and contrast these methods in terms of their efficiency and selectivity.
7. Describe the hydrolysis of alkyl cyanides to aldehydes using acid or base catalysis. Give an example of this reaction and describe the reaction mechanism involved.
8. Describe the ozonolysis of alkenes to aldehydes using ozone and reducing agents, such as dimethyl sulfide or zinc. Give an example of this reaction and describe the reaction mechanism involved.
9. Describe the Cannizzaro reaction, which involves the disproportionation of an aldehyde to form a carboxylic acid and an alcohol. Explain the conditions required for this reaction to occur and give an example of this reaction.
10. Describe the reaction of nitriles with reducing agents, such as lithium aluminum hydride or sodium borohydride, to form aldehydes. Give an example of this reaction and describe the reaction mechanism involved.

CARBOXYLIC ACID AND ITS DERVATIVES

1. Describe the structure and properties of carboxylic acids. How do they differ from alcohols and aldehydes/ketones?
2. Explain the process of preparing carboxylic acids from alcohols, aldehydes/ketones, and alkylbenzenes. Provide examples of each method.
3. Describe the reactions of carboxylic acids with metals, bases, and alcohols to form salts, esters, and acid anhydrides, respectively. Provide examples of each reaction.
4. Describe the hydrolysis of esters and acid anhydrides to form carboxylic acids. What are the conditions required for this reaction to occur?
5. Explain the formation of amides from carboxylic acids and amines. What is the mechanism of this reaction?
6. Describe the reactions of carboxylic acids with thionyl chloride and phosphorus pentachloride to form acid chlorides. What are the uses of acid chlorides in organic synthesis?
7. Explain the nucleophilic acyl substitution reactions of carboxylic acid derivatives, such as acid chlorides, acid anhydrides, esters, and amides. What factors affect the reactivity of these compounds in these reactions?
8. Describe the Claisen condensation reaction, which involves the formation of a β-ketoester from two ester molecules. What are the conditions required for this reaction to occur, and what is the mechanism involved?
9. Describe the Fischer esterification reaction, which involves the formation of an ester from a carboxylic acid and an alcohol. What are the conditions required for this reaction to occur, and what is the mechanism involved?
10. Explain the reaction of carboxylic acids with Grignard reagents to form carboxylate salts. How can these salts be converted back to carboxylic acids?
11. Describe the structure and properties of methanoic acid. How does it differ from other carboxylic acids?
12. Explain the abnormal behavior of methanoic acid towards oxidation and reduction reactions. What are the products formed in each reaction?

AMINES AND NITRO COMPOUND

1. Define amines and describe their classification based on the number of substituents attached to the nitrogen atom.
2. Explain the preparation of primary, secondary, and tertiary amines from alcohols, alkyl halides, and amides, respectively. Provide examples of each method.
3. Describe the basicity of amines and the factors that affect their basic strength. How can the basicity of an amine be compared with that of another amine or an organic compound?
4. Explain the reaction of amines with acids to form salts. How can these salts be converted back to the free amine form?
5. Describe the diazonium coupling reaction, which involves the formation of azo dyes from aromatic amines and diazonium salts. What are the conditions required for this reaction to occur, and what is the mechanism involved?
6. Explain the Hofmann bromamide reaction, which involves the conversion of a primary amine to a primary amide by reaction with bromine and sodium hydroxide. What are the conditions required for this reaction to occur, and what is the mechanism involved?
7. Describe the Gabriel phthalimide synthesis, which involves the conversion of a primary alkyl halide to a primary amine by reaction with phthalimide and sodium hydroxide. What are the conditions required for this reaction to occur, and what is the mechanism involved?
8. Explain the mechanism of the reductive amination reaction, which involves the formation of a primary, secondary, or tertiary amine from an aldehyde or ketone and a primary or secondary amine. What are the conditions required for this reaction to occur, and what is the role of the reducing agent?
9. Define nitro compounds and describe their classification based on the number and position of nitro groups in the molecule.
10. Explain the preparation of nitroalkanes, nitroarenes, and nitrophenols from the corresponding alkyl halides, aromatic compounds, and phenols, respectively. Provide examples