Aldehydes, Ketones and Carboxylic Acids

CBSE Class 12 Chemistry · every board question from this chapter, 2022–2026 · 54 of them repeated across years

• Which of the reactions is used in the conversion of a ketone into hydrocarbon?2026asked 3×
• Which of the following product is formed when salicylic acid is treated with (CH 3 CO) 2 O in the presence of acid?2026
• Which of the following Grignard Reagent will be used to prepare when treated with methanal?2026
• Assertion: All aliphatic aldehydes give a positive Fehling's test. Reason (R): Aliphatic aldehydes are reduced by Fehling's…2026asked 3×
• Gives the structures of A, B and C in the following reactions:2026
• How do you convert the following? Toluene to Benzaldehyde Benzoyl chloride to Acetophenone Bromobenzene to Benzoic acid []2026
• What happens when: Propanenitrile is treated with phenyl magnesium bromide followed by hydrolysis? p-fluorotoluene is treated…2026asked 3×
• Give reasons for the following: Carboxylic acids have higher boiling point than alcohols of comparable molecular masses. Alpha (…2026asked 3×
• Write the reaction involved in 1+1+1 Rosenmund's reduction Cannizzaro's reaction Hell - Volhard - Zelinsky reaction2026asked 3×
• How do you convert the following? Benzene to m-Nitroacetophenone Bromobenzene to 1-Phenylethanol But-3-en-2-one to…2026
• How do you convert the following? Acetophenone to Benzoic acid Acetonitrile to Acetone Benzoic acid to Benzene2026
• (i) Arrange the following compounds in increasing order of their acidic strengths: (ii) Why is CH 3 CHO more reactive than…2026asked 3×
• (i) An organic compound (X) has the molecular formula C 5 H 10 O. Draw structures for (X) if it: 3 + 2 (I) does not give Tollen's…2026asked 3×
• How will you convert the following: 3 + 2 (i) Propanone to Propene (ii) Benzoic acid to Benzaldehyde (iii) Benzene to…2026asked 3×
• (i) How will you bring about the following conversions: (I) Bromobenzene to 1-phenylethanol (II) Benzene to m-nitroacetophenone…2026asked 3×
• (i) Write the product(s) when: (I) One mol of ethanal is treated with 1 mol of CH 3 OH in the presence of dry HCl gas. (II)…2026asked 3×
• Which of the following aldehydes will undergo Cannizzaro reaction?2025asked 3×
• The acid formed when propyl magnesium bromide is treated with CO 2 followed by acid hydrolysis is:2025asked 3×
• CH 3 CH 2 CHO and CH 3 CH 2 COOH can be distinguished by:2025asked 3×
• Assertion: The solubility of aldehydes and ketones in water decreases with increase in size of the alkyl group. Reason (R):…2025asked 3×
• Draw the structures of product(s) in each of the following reactions:2025
• Would you expect benzaldehyde to be more reactive or less reactive in nucleophilic addition reactions than propanal? Justify your…2025asked 3×
• Give a simple chemical test to distinguish between 3-pentanone and 2-pentanone. Write an equation for Clemmensen reduction.2025
• Write the structures of the main products of the following reactions:2025
• How can acetaldehyde be prepared from acetyl chloride? Propanal is more reactive than propanone towards nucleophilic addition…2025
• Carboxylic acid is more acidic than phenol. Give reason. Give a chemical test to distinguish between benzaldehyde and…2025
• Write the products formed in the following reactions: CH 3 CHO+NH 2 CONHNH 2 → 1 CH 3 CHO dil. NaOH 1 CH 3 COOH [H 2 O]Cl 2 / redP2025
• Explain the following reactions and write chemical equation involved: Wolff-Kishner reduction Etard reaction Cannizzaro reaction…2025asked 3×
• An aromatic compound 'A' with molecular formula C 8 H 8 O gives positive 2,4-DNP test. It gives yellow precipitate. of compound…2025asked 2×
• Give reasons for the following: Benzoic acid does not undergo Friedel-Crafts reaction. HCHO is more reactive than CH 3 CHO…2025asked 3×
• Identify P, Q and R in the following reaction sequence:2025
• A compound with molecular formula C 4 H 5 N on reduction with DIBAL-H followed by hydrolysis, gives a compound. Compound gives…2025asked 3×
• An organic compound 'A' (molecular formula C 8 H 8 O ) gives 2,4-DNP test. It does not give Tollen's test, but gives a yellow…2025
• Write structure of the products of the following reactions:2025
• A compound 'A' with molecular formula C 4 H 8 O gives positive 2,4-DNP test. It gives yellow precipitate of compound 'B' on…2025
• (i) Complete the following reactions by writing the structure of the main products: (I) (II) (CH 3) 2 Cd+2 CH 3 COCl → (III) (ii)…2025asked 3×
• Give IUPAC name of CH 3-CH=CH-CHO. Give a simple chemical test to distinguish between propanal and propanone. How will you…2025asked 2×
• Give IUPAC name of CH 3-CH=CH-CHO. Give a simple chemical test to distinguish between propanal and propanone. 1 How will you…2025
• (i) Identify A, B and C in the following reactions: (ii) Give reasons for the following: (I) Carboxylic acids do not give the…2025asked 3×
• (i) An organic compound (X) having molecular formula C 5 H 10 O can show various properties depending on its structures. Draw…2025asked 3×
• Carry out the following conversions: (2+3=5) (i) Ethanal to But-2-enal (ii) Propanoic acid to ethane An alkene A with molecular…2025asked 3×
• Which of the following compounds will give a ketone on oxidation with chromic anhydride (CrO 3)?2024
• Which of the following is the strongest acid?2024
• The product formed as a result of reaction of CH 3 MgBr and CO 2 followed by hydrolysis is:2024
• Rosenmund reduction is used for the preparation of Aldehydes. The catalyst used in this reaction is2024asked 3×
• Which of the following contains sp^2 hybridised carbon bonded to X?2024
• Which one of the following compounds has the lowest pK a value?2024
• Which of the following Grignard reagent will be used with methanal to prepare2024
• Decarboxylation of sodium benzoate on heating with soda lime gives:2024
• Acetic acid reacts with PCl 5 to give:2024
• The formation of cyanohydrin from an aldehyde is an example of:2024
• Nucleophilic addition of Grignard reagent to ketones followed by hydrolysis with dilute acids forms:2024asked 3×
• Assertion: Fluoroacetic acid is stronger acid than chloroacetic acid. Reason (R): This is due to greater electron withdrawing…2024
• Assertion: Benzoic acid does not undergo Friedel - Crafts reaction. Reason (R): Carboxyl group is deactivating and the catalyst…2024asked 3×
• Assertion: The pK a of O 2 N-CH 2-COOH is lower than that of CH 3-COOH. Reason (R): -NO 2 group shows electron withdrawing effect…2024
• Assertion: The pK a of ethanoic acid is lower than that of Cl-CH 2-COOH. Reason (R): Chlorine shows electron withdrawing (-I)…2024
• Write the chemical equations when: Pentan-3-one is treated with H 2 N-NH 2 followed by heating with KOH in high boiling solvent…2024
• Write the stepwise mechanism of nucleophilic addition reactions in the carbonyl compounds. OR How will you convert the following:…2024asked 3×
• Write the chemical equations when: Ethanal is treated with 2,4-dinitrophenylhydrazine? Propanone is treated with Zn(Hg) and conc.…2024
• Write the chemical equation when: Butan-2-one is treated with Zn(Hg) and conc. HCl. Two molecules of benzaldehyde are treated…2024
• Write the reaction involved in the following: Wolff-Kishner reduction Decarboxylation reaction Cannizzaro reaction2024asked 3×
• Give chemical tests to distinguish between the following pairs of compounds: (i) Phenol and Benzoic acid (ii) Propanal and…2024asked 3×
• How will you bring about the following conversions? (any three) Benzoic acid to Benzaldehyde Ethanal to Propanone Acetophenone to…2024asked 3×
• Compound (C 6 H 12 O 2) on reduction with LiAlH 4 gives two compounds and. The compound on oxidation with PCC gives compound…2024asked 3×
• An organic compound with the molecular formula C 9 H 10 O forms 2, 4-DNP derivative, reduces Fehling solution and undergoes…2024asked 3×
• (i) Write the major product(s) in the following reactions: (2) (3) (ii) Give simple chemical tests to distinguish between the…2024asked 3×
• (i) Account for the following: (1) Oxidation of aldehydes is easier as compared to ketones. (2) The alpha ( α ) hydrogen atoms of…2024asked 3×
• A compound with molecular formula C 5 H 10 O, forms a phenyl hydrazone and gives negative Tollens'and iodoform tests. The…2023
• The reactivities of the carbonyl compounds HCHO (I), CH 3 CHO (II) and CH 3 COCH 3 (III) towards nucleophilic addition reaction…2023
• Which of the following reagents would one choose to transform CH 3 COCl into acetone?2023
• The reagent that can be used to distinguish acetophenone and benzophenone is2023
• Which of the following does not give Cannizaro reaction?2023
• Which of the following is most reactive in nucleophilic addition reactions?2023
• Which of the following does not give aldol condensation reaction?2023
• Aldehydes and ketones react with hydroxylamine to form 12023
• Which one of the following has lowest pK a value?2023asked 2×
• Which of the following compounds will undergo self-condensation in the presence of dilute NaOH solution?2023
• This reaction is known as:2023
• C 6 H 5 CHO+CH 3 COCH 3 [Δ]OH^- C 6 H 5 CH=CH-COCH 3 This reaction is known as:2023
• Which of the following is an 'Acetal'?2023
• Assertion: Acetic acid but not formic acid can be halogenated in presence of red P and C l 2. Reason (R): Acetic acid is a weaker…2023
• Assertion: The final product in Aldol condensation is always α, β - unsaturated carbonyl compound. Reason (R): α, β -unsaturated…2023
• Give the structures and IUPAC name of the products expected from the following reactions: Reaction of methanal with followed by…2023
• Write the structures and IUPAC names of the products expected from the following reactions: Reaction of methanal with (CH 3) 2…2023
• Do the following conversions in not more than two steps: 2 × 1 CH 3 COOH to CH 3 COCH 3 to2023
• Give reasons for the following: Carboxylic carbon is less electrophilic than Carbonyl carbon of aldehydes and ketones. Propanal…2023asked 2×
• Write the products of the following reactions: (i) (ii) OR Do the following conversions in not more than two steps: (i) Toluene…2023asked 3×
• Give reasons: Formic acid is a stronger acid than acetic acid. Alpha ( α ) -Hydrogens of aldehydes and ketones are acidic.2023
• Explain why: (i) Carboxyl group in benzoic acid is meta directing. (ii) Sodium bisulphite is used for the purification of…2023asked 2×
• Explain why: (i) Carboxyl group in benzoic acid is meta directing. (ii) Sodium bisulphite is used for the purification of…2023
• The carbon - oxygen double bond is polarised in aldehydes and ketones due to higher electronegativity of oxygen relative to…2023asked 3×
• (i) Carry out the following conversions: (1) Ethanal to But-2-en-1-al (2) Propanoic acid to 2-chloropropanoic acid (ii) An alkene…2023asked 2×
• Draw structure of the 2,4-dinitrophenylhydrazone of benzaldehyde. Which acid of the following pair is a stronger acid? or Write…2023asked 3×
• (i) Write the reaction involved in Cannizaro's reaction. 1+1+3=5 (ii) Why are the boiling point of aldehydes and ketones lower…2023asked 3×
• (i) An organic compound (X) having molecular formula C 5 H 10 O can show various properties depending on its structures. Draw…2023asked 3×
• (i) Carry out the following conversions: (1) Ethanal to But-2-en-1-al (2) Propanoic acid to 2-chloropropanoic acid (ii) An alkene…2023
• Arrange the following compounds in the increasing order of their property indicated: (Any two) (i) Acetaldehyde, Benzaldehyde,…2022
• Arrange the following compounds in increasing order of their property as indicated in bracket: (Any two ) (i) CH 3-CHO,,…2022
• How will you carry out the following conversions: (Any two) (i) Propanal to Propane (ii) Ethanal to But-2-enal (iii) Ethanoic…2022
• Predict the products formed when CH 3 CH 2 CHO reacts with the following reagents: (Any two) (i) PhMgBr and then H 3 O^+ (ii)…2022
• Predict the reagent for carrying out the following transformations: (Any two) (i) Benzoyl chloride to Benzaldehyde (ii) Ethanal…2022
• Predict the products formed when CH 3 CHO reacts with the following reagents: (Any two) (i) CH 3 MgBr and then H 3 O^+ (ii)…2022
• Arrange the following in the increasing order of the property mentioned: CH 3 COOH, ClCH 2 COOH, FCH 2 COOH (Acid strength) CH 3…2022
• Arrange the following in the increasing order of their property indicated: Ethanal, Propanone, Propanal, Butanone (reactivity…2022asked 2×
• Explain the following reactions: Clemmensen reduction Stephen reaction2022
• Write the products formed when benzaldehyde reacts with the following reagents (Any two): (i) CH 3 CHO in presence of dilute NaOH…2022
• Give reasons for the following statements: (Any two) (i) Benzaldehyde is less reactive than propanal in nucleophilic addition…2022
• Write reasons for the following statements: (i) Benzoic acid does not undergo Friedel-Crafts reaction. (ii) Oxidation of…2022asked 3×
• Explain the following reactions: Wolff Kishner reduction Cannizzaro reaction2022asked 2×
• (i) (CH 3) 3 C-CHO does not undergo aldol condensation. Why? (ii) Distinguish between Acetophenone and Benzophenone with the help…2022
• Predict the products in the following reactions: (i) CH 3MgBr + CO 2 H 3O^+ (ii) CH 3CN [ H 2O] DIBAL-H (iii) [Δ]H 3O^+ OR…2022
• Write the major products in the following: (i) [273-283 K]HNO 3 + H 2SO 4 (ii) + NaOH [Δ]CaO (iii) NH 2OH OR (i) Oxidation of…2022asked 3×
• Write the equations involved in the following reactions: (i) Cannizzaro reaction (ii) Aldol condensation (iii)…2022
• A compound 'A' (C 2 H 4 O) on oxidation gives 'B' (C 2 H 4 O 2). 'A' undergoes Iodoform reaction to give yellow precipitate and…2022asked 2×
• An organic compound 'X' with the molecular formula C 5 H 10 O forms 2,4-DNP derivative, does not reduce Tollens' reagent but…2022asked 3×
• What happens when (i) Propanone is treated with CH 3 MgBr and then hydrolysed? (ii) Ethanal is treated with excess ethanol and…2022asked 2×
• Write the equation involved in the following reactions: (i) Rosenmund reduction (ii) Etard reaction (iii) Stephen reaction OR (i)…2022
• Complete the following: (i) CH 3 CN [ 2. H 2 O] 1. A 1 H(i-Bu) 2^′ A^′ [H^+]H 2 N-OH 'B' (ii) Write IUPAC name of the following…2022asked 3×
• (i) Which acid of the following pair would you expect to be stronger? F-CH 2-COOH or CH 3-COOH (ii) Arrange the following…2022asked 3×
• Read the passage given below and answer the questions that follow: Aldehydes, ketones and carboxylic acids are some of the…2022asked 3×

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