SaitechAI – Aldehydes, Ketones & Carboxylic Acids

Class 12 CBSE • 100 Frequently Asked One-Mark Questions (No Answers)

1-Mark Question Bank
  1. Write the IUPAC name of CH₃–CH₂–CHO.
  2. Draw the structural formula of 3-oxopentanal.
  3. Name the reagent used in Tollens' test.
  4. What is the purpose of Tollens’ reagent in organic analysis?
  5. Draw the structure of 4-chloropentan-2-one.
  6. Which functional group is present in ketones?
  7. Why do aldehydes generally show higher reactivity toward nucleophilic addition than ketones?
  8. Give a chemical test to distinguish between an aldehyde and a ketone.
  9. What is the IUPAC name of HCOOH?
  10. What is the IUPAC name of CH₃–COOH?
  11. Why do carboxylic acids have higher boiling points than aldehydes or ketones of comparable molar mass?
  12. Which intermolecular force is chiefly responsible for the high boiling point of carboxylic acids?
  13. Draw the structure of p-methylbenzaldehyde.
  14. What is an α-hydrogen with respect to carbonyl compounds?
  15. Name the reaction in which aldehydes without α-hydrogen atoms react in alkali to undergo simultaneous oxidation and reduction.
  16. Which aldehydes undergo the reaction mentioned in Q15 – aromatic, aliphatic or both?
  17. Why is the carbonyl carbon in carboxylic acids less electrophilic than that in aldehydes or ketones?
  18. What gas evolves when a carboxylic acid is treated with NaHCO₃?
  19. Write a test to distinguish between benzoic acid and phenol.
  20. Give the IUPAC name of 4-hydroxypentan-2-one.
  21. What is the general formula of aldehydes?
  22. What is the general formula of ketones?
  23. What is the general formula of carboxylic acids?
  24. Draw the structure of 2-methylbutanal.
  25. What product is obtained when a carboxylic acid is heated with soda-lime (NaOH + CaO)?
  26. Name the process described in Q25.
  27. Name any one reagent used in the reduction of aldehydes and ketones to alcohols.
  28. What is the IUPAC name of 1-phenylpentan-1-one?
  29. Name the test in which acetaldehyde is warmed with I₂ and NaOH.
  30. What kind of carbonyl compound gives a positive iodoform test?
  31. Why does acetone give iodoform test but benzophenone does not?
  32. Arrange ethanal, propanal, propanone and butanone in increasing order of reactivity toward nucleophilic addition.
  33. Which is more acidic: CH₃COOH or ClCH₂COOH?
  34. Why is ClCH₂COOH more acidic than CH₃COOH?
  35. What is the common name of CH₃CHO?
  36. What is the common name of CH₃COCH₃?
  37. Which functional group is present in formaldehyde (HCHO)?
  38. Does formaldehyde reduce Tollens’ reagent?
  39. Does acetone reduce Tollens’ reagent?
  40. Give an example of a ketone that shows iodoform test.
  41. Why do ketones generally not give Tollens’ test?
  42. What happens when an aldehyde without α-hydrogen is treated with concentrated alkali? (Name the reaction.)
  43. Name one test that can distinguish between propanal and propanone.
  44. Suggest a simple chemical test to distinguish between ethanoic acid and methanoic acid.
  45. Which acid will give Tollens’ test: HCOOH or CH₃COOH?
  46. Give the IUPAC name of 3-hydroxybutanoic acid.
  47. What is meant by “α-carbon” in a carbonyl compound?
  48. Draw the structural formula of 1-phenylpropan-1-one.
  49. Which is more reactive toward nucleophilic addition: aldehyde or ketone?
  50. Why does a carboxylic acid not show typical nucleophilic addition reactions of the carbonyl group?
  51. What is the pH nature of dilute solutions of most carboxylic acids: acidic, neutral or basic?
  52. Among ethanol, ethanal and ethanoic acid, which has the highest boiling point?
  53. Among methanal, methanol and methanoic acid, which is most soluble in water?
  54. Why are lower aldehydes and ketones soluble in water?
  55. Why does solubility in water decrease as the alkyl chain length increases in carboxylic acids and ketones?
  56. What is the IUPAC name of CH₃–CH₂–CO–CH₂–CH₃?
  57. Does benzaldehyde give iodoform test?
  58. Does acetophenone give iodoform test?
  59. Write the structural formula of 3-methylpentanal.
  60. What is the IUPAC name of CH₃–CH₂–COOH?
  61. What type of reaction occurs when a ketone is reduced by catalytic hydrogenation to an alcohol?
  62. What happens when you oxidize propanone with a mild oxidizing agent?
  63. What happens when you oxidize propanal with a mild oxidizing agent?
  64. Why are ketones more resistant to oxidation compared to aldehydes?
  65. Name a reagent that oxidizes primary alcohols to carboxylic acids via aldehyde intermediate.
  66. What is formed when a carboxylic acid reacts with SOCl₂ (thionyl chloride)?
  67. What functional group is present in an acid chloride?
  68. Suggest a test to distinguish between benzaldehyde and benzoic acid.
  69. What is meant by the −I (inductive) effect in substituted carboxylic acids?
  70. Why is 4-nitrobenzoic acid a stronger acid than benzoic acid?
  71. What is meant by an “unsaturated ketone”?
  72. Give one example of an unsaturated ketone.
  73. What is the product when an α,β-unsaturated carbonyl compound undergoes catalytic hydrogenation?
  74. What is the effect of an electron-withdrawing group (such as −NO₂) on the acidity of benzoic acid?
  75. Define “methyl ketone”.
  76. Does formic acid show iodoform test?
  77. Give the IUPAC name of CH₃–CH₂–CO–CH₃.
  78. What is the general mechanism type for nucleophilic addition to carbonyl compounds?
  79. Name any two nucleophiles that can add to a carbonyl carbon.
  80. Why do aldehydes get oxidized easily but ketones do not on mild oxidation?
  81. What product is obtained when benzaldehyde is oxidized with KMnO₄?
  82. What product is obtained when ethanal is oxidized with Tollens’ reagent?
  83. What happens when you treat a ketone containing α-hydrogen with Br₂ in the presence of base?
  84. Name the reaction mentioned in Q83.
  85. Which will be more volatile — propanal or propanone?
  86. Write the structural formula of 2,4-dimethylpentan-3-one.
  87. Give the IUPAC name of benzaldehyde.
  88. What is the common name of CH₃–CO–CH₃?
  89. What type of product is formed when a carbonyl compound reacts with 2,4-DNP reagent?
  90. Does a carboxylic acid react with 2,4-DNP reagent to give a positive test?
  91. What gaseous product is formed when a sodium salt of carboxylic acid is strongly heated?
  92. What is meant by Clemmensen reduction?
  93. Which carbonyl compounds can undergo Wolff–Kishner reduction?
  94. Write the structural formula of 2-butanone.
  95. Write the structural formula of 2-pentanone.
  96. What is meant by “isomeric ketones”? Give one example.
  97. What is meant by a “saturated aldehyde”? Give one example.
  98. What happens when methanoic acid is oxidized with acidified dichromate?
  99. Among HCOOH, CH₃COOH and CH₃CH₂COOH, which is the strongest acid?
  100. What is the effect of a −I group on the acidic strength of a carboxylic acid?
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