This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Chemistry Part Ii > Class 12 Chemistry (Part Ii) Chapter 12 Aldehydes – Quiz 3 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part Ii) Chapter 12 Aldehydes Quiz 3 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Oxidation of secondary alcohol with chromic acid results in the production of ..... A) A ketone. B) An ester. C) An aldehyde. D) An alcohol. Show Answer Correct Answer: A) A ketone. 2. Propanone is very soluble in water because A) It is non-polar. B) It can form hydrogen bond with water molecule. C) Water is a polar solvent. D) The dipole-dipole interactions are weak between propane and water. Show Answer Correct Answer: B) It can form hydrogen bond with water molecule. 3. The compound among the following NOT oxidised by Fehling solution is ..... A) Benzaldehyde. B) Acetaldehyde. C) $\alpha$-hydroxy ketone. D) Formic acid. Show Answer Correct Answer: A) Benzaldehyde. 4. What is the key chemical difference between aldehydes and ketones? A) Aldehydes are acidic but ketones are not. B) Ketones contain oxygen but aldehydes do not. C) Aldehydes are easily oxidised, ketones are not. D) Ketones react more readily with oxidising agents. Show Answer Correct Answer: C) Aldehydes are easily oxidised, ketones are not. 5. Aldehydes can be prepared from conversion of arines. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 6. Which of the following is/are correct use(s) of alcohols?I. FuelII. SolventIII. Starting material for plastic substances A) I only. B) I and II only. C) I and III only. D) II and III only. Show Answer Correct Answer: B) I and II only. 7. What is the key difference between the hydration of alkynes and alkenes in terms of products formed? A) Alkynes undergo a single addition of water to form alcohols. B) Alkenes undergo two additions of water molecules to form ketones. C) Alkynes form alcohols directly without any addition of water. D) Alkynes undergo two additions of water molecules, forming ketones or aldehydes, while alkenes undergo a single addition to form alcohols. Show Answer Correct Answer: D) Alkynes undergo two additions of water molecules, forming ketones or aldehydes, while alkenes undergo a single addition to form alcohols. 8. Which of the following compounds is the most acidic? A) Butane. B) 2-Butanone. C) Butanal. D) None of the above. Show Answer Correct Answer: C) Butanal. 9. What is the purpose of the Gattermann-Koch reaction in aldehyde and ketone synthesis? A) To introduce a formyl group onto an aromatic ring for aldehyde and ketone synthesis. B) To remove a hydroxyl group from an aromatic ring. C) To convert an alkene into an aldehyde. D) To introduce a methyl group onto an aliphatic chain. Show Answer Correct Answer: A) To introduce a formyl group onto an aromatic ring for aldehyde and ketone synthesis. 10. Which of the following is an isomer of acetone? A) Propanol. B) Propanal. C) Ethanal. D) Ethanol. Show Answer Correct Answer: B) Propanal. 11. Which is the strongest acid out of these 4 compounds? A) C$_{6}$H$_{5}$OH. B) CH$_{3}$CHFCOOH. C) CH$_{2}$BrCH$_{2}$COOH. D) CH$_{3}$CH$_{2}$COOH. Show Answer Correct Answer: B) CH$_{3}$CHFCOOH. 12. Which carboxylic acid is most acidic? A) CH$_{3}$CH$_{2}$CH$_{2}$COOH. B) CH$_{3}$CH$_{2}$CH(Cl)COOH. C) ClCH$_{2}$CH$_{2}$CH$_{2}$COOH. D) CH$_{3}$CH(Cl)CH$_{2}$COOH. Show Answer Correct Answer: B) CH$_{3}$CH$_{2}$CH(Cl)COOH. 13. Aldehydes and ketones can be oxidized. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 14. The IUPAC name for CH3CH2CH2CHO is: A) Ethanal. B) Pentanal. C) Butanal. D) Propanal. Show Answer Correct Answer: C) Butanal. 15. Test for aldehyde A) Add Tollen's reagent, warm to produce a silver mirror. B) Add damp red litmus paper which turns blue. C) Add silver nitrate which produces a white precipitate. D) Add bromine water which changes from orange to colourless. Show Answer Correct Answer: A) Add Tollen's reagent, warm to produce a silver mirror. 16. What functional group is present in the intermediate formed during the reaction of Grignard reagents with carbonyl compounds? A) Alkoxide group (-OR). B) Amine group (-NH2). C) Carboxyl group (-COOH). D) Hydroxide group (-OH). Show Answer Correct Answer: A) Alkoxide group (-OR). 17. When aldehyde is heated with Fehling's solution, it gives a precipitate of A) Cu$_{2}$O & CuO. B) Cu$_{2}$O. C) Cu. D) CuO. Show Answer Correct Answer: B) Cu$_{2}$O. 18. Which organ breaks down alcohol? A) Liver. B) Heart. C) Lungs. D) Kidneys. Show Answer Correct Answer: A) Liver. 19. Compare the boiling points of carboxylic acids with aldehydes and ketones. A) Carboxylic acids have higher boiling points than aldehydes and ketones. B) Aldehydes and ketones have higher boiling points than carboxylic acids. C) Carboxylic acids have lower boiling points than aldehydes and ketones. D) Aldehydes and ketones have similar boiling points to carboxylic acids. Show Answer Correct Answer: A) Carboxylic acids have higher boiling points than aldehydes and ketones. 20. Which of the following species can attack the carbon atom in the carbonyl group, C=O? A) Br$_{2}$. B) CN$^{-}$. C) NO$_{2}$$^{+}$. D) Cl. Show Answer Correct Answer: B) CN$^{-}$. 21. What is the purpose of the Rosenmund reaction in aldehyde preparation? A) To convert acyl chlorides to aldehydes. B) To convert aldehydes to carboxylic acids. C) To convert aldehydes to acyl chlorides. D) To convert aldehydes to ketones. Show Answer Correct Answer: A) To convert acyl chlorides to aldehydes. 22. Type of mechanism that aldehydes and ketones undergo A) Nucleophilic addition. B) Electrophilic addition. C) Nucleophilic substitution. D) Electrophilic substitution. Show Answer Correct Answer: A) Nucleophilic addition. 23. What type of chemical reaction do aldehydes undergo with Tollens' reagent? A) Redox reaction. B) Decomposition reaction. C) Neutralization reaction. D) Combustion reaction. Show Answer Correct Answer: A) Redox reaction. 24. Which of the following is an example of a ketone? A) Ethanal. B) Propanone. C) Methanol. D) Ethanoic acid. Show Answer Correct Answer: B) Propanone. 25. When benzyl alcohol is oxidised with KMnO$_{4}$, the product obtained is which of the following compound? A) Benzaldehyde. B) Benzoic acid. C) CO$_{2}$ and H$_{2}$O. D) Benzophenone. Show Answer Correct Answer: B) Benzoic acid. 26. Aldehyde reacts with Tollen's reagent forming: A) Purple solution. B) Silver mirror. C) Yellow precipitate. D) Brick-red precipitate. Show Answer Correct Answer: B) Silver mirror. 27. The Pistachio flavor of ketone present in A) Acetone. B) Acetophenone. C) Benzophenone. D) Ethyl, methyl ketone. Show Answer Correct Answer: B) Acetophenone. 28. Provide the IUPAC name for the following compound:CH3COCH3. A) Butanone. B) Propanone. C) Ethanal. D) Methanol. Show Answer Correct Answer: B) Propanone. 29. What type of hybridization occurs in carbon atom of the carbonyl group of aldehydes and ketones? A) Sp$^{3}$d$^{2}$. B) Sp$^{3 }$. C) Sp. D) Sp$^{2}$. Show Answer Correct Answer: D) Sp$^{2}$. 30. What is the IUPAC name for the following compound:CH3CHO? A) Propanal. B) Ethanal. C) Methanal. D) Ethanoic acid. Show Answer Correct Answer: B) Ethanal. 31. Which of the following compounds will give a positive Fehling's test? A) Methanal. B) Propanone. C) Ethanoic acid. D) Butanone. Show Answer Correct Answer: A) Methanal. 32. The common name for CH3CH2COOH is: A) Acetic acid. B) Formic acid. C) Propionic acid. D) Butyric acid. Show Answer Correct Answer: C) Propionic acid. 33. Which interaction has the greatest effect on the physical properties of carboxylic acids? A) Covalent bond. B) Hydrogen bond. C) VanderWaals force. D) Dipole-dipole force. Show Answer Correct Answer: B) Hydrogen bond. 34. C$_{6}$H$_{5}$CH=CHCHO is A) Benzaldehyde. B) Salicyldehyde. C) Cinnamaldehyde. D) None of these. Show Answer Correct Answer: C) Cinnamaldehyde. 35. How many hydrogens does butane have? A) 8. B) 6. C) 10. D) 12. Show Answer Correct Answer: C) 10. 36. When reacted with a strong reducing agent, aldehydes turn into A) Primary alcohols. B) Ketones. C) Secondary alcohols. D) Carboxylic acids. Show Answer Correct Answer: A) Primary alcohols. 37. What is the red precipitate formed in Fehling's test? A) Copper(II) oxide. B) Copper carbonate. C) Copper metal. D) Copper(I) oxide (Cu2O). Show Answer Correct Answer: D) Copper(I) oxide (Cu2O). 38. Why are aldehydes more reactive than ketones towards nucleophilic additions? A) Aldehydes have two electron donating groups attached to it. B) Aldehyde is less sterically hindered than ketone. C) Ketones are not carbonyl compounds. D) Aldehydes have more electron-withdrawing groups. Show Answer Correct Answer: B) Aldehyde is less sterically hindered than ketone. 39. What is the first step of a base catalyzed nucleophillic addition reaction of a ketone? A) Protonate the carbonyl group. B) Loss of leaving group. C) Nucleophillic attack. D) Proton transfer. Show Answer Correct Answer: C) Nucleophillic attack. 40. The ozonolysis of an alkene can produce: A) Aldehydes only. B) Ketones only. C) A mixture of aldehydes and ketones. D) Carboxylic acids only. Show Answer Correct Answer: C) A mixture of aldehydes and ketones. 41. Acidified potassium dichromate (VI) has the following colour change during oxidation A) Colourless to silver. B) Blue to red. C) Orange to green. D) Green to orange. Show Answer Correct Answer: C) Orange to green. 42. State the conditions required for the Tollens' silver mirror test. A) A solution of silver nitrate, ammonia, and a ketone compound. B) A solution of silver nitrate, sodium hydroxide, ammonia, and an aldehyde compound (including reducing sugars). C) A solution of silver sulfate, ammonia, and an aldehyde compound. D) A solution of silver chloride, ammonia, and an aldehyde compound. Show Answer Correct Answer: B) A solution of silver nitrate, sodium hydroxide, ammonia, and an aldehyde compound (including reducing sugars). 43. Which of the following substances produces 3-pentanol when reduced by H$_{2}$? A) Pentanal. B) Butanal. C) Diethyl ketone. D) Dimethyl ketone. E) Methyl propyl ketone. Show Answer Correct Answer: C) Diethyl ketone. 44. Colour change observed when acidified potassium dichromate reacts with an alcohol, aldehyde or ketone A) Green to orange. B) Green to colour less. C) Orange to green. D) Orange to colourless. Show Answer Correct Answer: C) Orange to green. 45. In Friedel-Crafts Acylation, what type of compound is acylated to form ketones? A) Alcohols. B) Alkanes. C) Aldehydes. D) Benzene rings. Show Answer Correct Answer: D) Benzene rings. 46. How can a secondary alcohol be oxidized to form a ketone? A) Heating the secondary alcohol with water. B) Using a strong oxidizing agent such as potassium dichromate (K2Cr2O7) in the presence of an acid like sulfuric acid (H2SO4). C) Using a reducing agent such as potassium dichromate (K2Cr2O7). D) Adding a base like sodium hydroxide (NaOH). Show Answer Correct Answer: B) Using a strong oxidizing agent such as potassium dichromate (K2Cr2O7) in the presence of an acid like sulfuric acid (H2SO4). 47. HVZ reaction involves A) Substitution reaction in hydrocarbon part of carboxylic acid. B) Cleavage of C-OH bond of carboxylic acid. C) Reduction reaction of carboxylic group. D) Cleavage of O-H bond of carboxylic acid. Show Answer Correct Answer: A) Substitution reaction in hydrocarbon part of carboxylic acid. 48. Which reagent is used to distinguish between aldehydes and ketones? A) Lucas reagent. B) Benedict's solution. C) Tollen's reagent. D) Grignard reagent. Show Answer Correct Answer: C) Tollen's reagent. 49. How do you produce a carboxylic acid? A) Oxidizing a secondary alcohol or a ketone. B) Oxidizing a primary alcohol or an aldehyde. C) Reducing a primary alcohol or aldehyde. D) Reducing a secondary alcohol or ketone. Show Answer Correct Answer: B) Oxidizing a primary alcohol or an aldehyde. 50. The simplest ketone has A) Three carbon atoms. B) Four carbon atoms. C) One carbon atom. D) Two carbon atoms. E) Five carbon atoms. Show Answer Correct Answer: A) Three carbon atoms. 51. When reacted with a strong reducing agent, ketones turn into A) Secondary alcohols. B) Primary alcohols. C) Ketones. D) Carboxylic acids. Show Answer Correct Answer: A) Secondary alcohols. 52. When performing recrystallisation to purify crystals, on what basis is the solvent selected? A) The crystals have a high solubility in hot solvent but a low solubility in cold solvent. B) The crystals have a high solubility in cold solvent but a low solubility in. C) The crystals must be highly soluble in both hot and cold solvent. D) It doesn't matter which solvent you use. Show Answer Correct Answer: A) The crystals have a high solubility in hot solvent but a low solubility in cold solvent. 53. What is the hybridization and geometry of aldehydes and ketones carbons? A) Sp2 and trigonal planar. B) Sp2 and linear. C) Sp3 and tetrahedral. D) Sp3 and linear. E) Sp2 and tetrahedral. Show Answer Correct Answer: A) Sp2 and trigonal planar. 54. Which of the following alcohols can be oxidised to 2-methyl-3-pentanone? A) (CH$_{3}$)$_{3}$CCH(OH)CH$_{3}$. B) (CH$_{3}$)$_{2}$CHCH(OH)CH$_{2}$CH$_{3}$. C) CH$_{3}$CH$_{2}$CH(OH)CH$_{3}$. D) CH$_{3}$CH(OH)CH$_{2}$CH$_{2}$CH$_{3}$. Show Answer Correct Answer: B) (CH$_{3}$)$_{2}$CHCH(OH)CH$_{2}$CH$_{3}$. 55. Which substance gives a positive Tollen's test? A) Propanone. B) Ethanal. C) Ethanoic acid. D) Methane. Show Answer Correct Answer: B) Ethanal. 56. Which type of carboxylic acid reduction leads to the formation of ketones? A) Oxidation of carboxylic acids to ketones. B) Reduction of carboxylic acids to ketones is typically achieved using milder reagents like DIBAL-H or borane. C) Reduction of carboxylic acids to aldehydes. D) Decarboxylation of carboxylic acids to alkanes. Show Answer Correct Answer: B) Reduction of carboxylic acids to ketones is typically achieved using milder reagents like DIBAL-H or borane. 57. What is the result of the hydration of alkynes in terms of functional groups? A) Aldehydes. B) Ketones. C) Alcohols. D) Esters. Show Answer Correct Answer: B) Ketones. 58. Which general conclusion can be drawn about carboxylic acids from these reactions? A) They behave as bases. B) They show acidic properties. C) They are oxidising agents. D) They do not react with metals. Show Answer Correct Answer: B) They show acidic properties. 59. The compound with highest boiling point in the following is ..... A) Butanoic acid. B) Butan-2-one. C) Butan-2-ol. D) Butanal. Show Answer Correct Answer: A) Butanoic acid. 60. What is the product formed when an aldehyde reacts with a primary amine? A) Amides. B) Imines. C) Ketones. D) Esters. Show Answer Correct Answer: B) Imines. ← PreviousNext →Related QuizzesScience QuizzesClass 12 QuizzesClass 12 Chemistry (Part Ii) Chapter 12 Aldehydes Quiz 1Class 12 Chemistry (Part Ii) Chapter 12 Aldehydes Quiz 2Class 12 Chemistry (Part Ii) Chapter 12 Aldehydes Quiz 4Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes QuizClass 12 Chemistry (Part Ii) Chapter 11 Alcohols QuizClass 12 Chemistry (Part Ii) Chapter 13 Amines QuizClass 12 Chemistry (Part Ii) Chapter 14 Biomolecules QuizClass 12 Chemistry (Part Ii) Chapter 15 Polymers Quiz 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books