Free Aldehydes and Ketones MCQs with Answers
679 Aldehydes and Ketones MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Aldehydes and ketones contain the polar carbonyl group, but aldehydes are generally more readily oxidised and more reactive than ketones. Coverage includes preparation by oxidation or reduction routes, nucleophilic addition of reagents such as hydrogen cyanide and bisulfite, and tests that distinguish aldehydes from ketones.
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679 questions · page 29 of 34
- A. 1
- B. 2
- C. 3
- D. 4
- E. None of the above
Explanation: First, substitute the symbols in the expression as follows:- means *, * means +, + means /, and / means -.This transforms the given…
Correct answer: 4- A. Statement I is the cause and statement II is its effect
- B. Statement II is the cause and statement I is its effect
- C. Both the statements I and II are independent causes
- D. Both the statements I and II are effects of independent causes
Explanation: An increase in government duty (a tax) on cars (Statement II) directly increases the cost for manufacturers.
Correct answer: Statement II is the cause and statement I is its effect- A. Benzaldehyde
- B. Acetaldehyde
- C. Formaldehyde
- D. Propanaldehyde
Explanation: Formaldehyde is the simplest aldehyde and is highly reactive towards nucleophiles.
Correct answer: Formaldehyde- A. HCHO < CH₃CHO < CH₃COCH₃ < CH₃COCH₃
- B. CH₃CH₂CHO < CH₃COCH₃ < CH₃CHO < HCHO
- C. HCHO < CH₃COCH₃ < CH₃CH₂CHO < CH₃CHO
- D. CH₃COCH₃ < CH₃CH₂CHO < CH₃CHO < HCHO
Explanation: Methyl group is electron donating group hence decreases reactivity
Correct answer: CH₃COCH₃ < CH₃CH₂CHO < CH₃CHO < HCHO- A. Aldol condensation
- B. Cannizzaro's reaction
- C. lodoform test
- D. Lucas test
Explanation: Iodoform test, as it specifically distinguishes between ethanal and propanal by their reactions with iodine and hydroxide ions to form or…
Correct answer: lodoform test- A. Reducing property.
- B. Oxidizing property.
- C. Neutralizing ability.
- D. Redox property.
Explanation: Aliphatic aldehydes form a brick-red precipitate with Fehling's solution. To an aldehyde solution, add Fehling's solution and boil.
Correct answer: Redox property.- A. Acetone
- B. Acetic acid
- C. Ethanol
- D. Ether
Explanation: Acetone is the correct answer. It is a solvent that effectively dissolves nail polish, making it easy to remove.
Correct answer: Acetone- A. Acetone
- B. Acetic acid
- C. Acetamide
- D. Acetic anhydride
Explanation: The reaction given is iodoform reactionAcetic acid, acetamide and acid anhydride don't undergo iodoform reaction
Correct answer: Acetone- A. Grignard reagent
- B. Tollen's reagent
- C. Fehling's reagent
- D. Sodium nitroprusside
Explanation: The carboxyl group of both aldehydes and ketones can react with Grignard reagents to give alcohols.
Correct answer: Grignard reagent- A. Manufacture of dyes
- B. Silvering of mirror
- C. Making formamint
- D. Antiseptic inhalent
Explanation: Uses of Fomaldehyde(i) It is used in the manufacture of resins like urea-formaldehyde and plasticssuch as bakelite.(ii) It is used in the…
Correct answer: Antiseptic inhalent- A. Acetaldehyde
- B. Acetone
- C. Butanone
- D. 3-pentanone
Explanation: Iodoform Test:The haloform reaction using iodine and aqueous sodium hydroxide is calledthe iodoform test.
Correct answer: 3-pentanone- A. Grignard reagent
- B. Tollen's reagent
- C. Fehling's reagent
- D. Benedict's reagent
Explanation: Grignard reagents add to aldehydes and ketones to form adducts which on hydrolysis with a dilute mineral acid (HCI, H2SO4) give alcohols.
Correct answer: Grignard reagent- A. Sugars
- B. Menthone
- C. Camphor
- D. Formamint
Explanation: Both ketones and aldehydes are present in sugars. Monosaccharides which contain an aldehyde group are known as aldoses, and those with a…
Correct answer: Sugars- A. H2SO4
- B. K2Cr207
- C. NaOH
- D. H20/H+
Explanation: Option C is correct since the aldol reaction happens in aldehydes and ketones if the compounds contain no less than one α-hydrogen.
Correct answer: NaOH- A. Formaldehyde
- B. Acetaldehyde
- C. Benzaldehyde
- D. Trimethyl acetaldehyde
Explanation: Cannizzaro's reaction is not given by aldehydes and ketones that have alpha hydrogen (hydrogen next to carbonyl carbon).
Correct answer: Acetaldehyde- A. Formaldehyde is a gas at room temperature
- B. Formaldehyde is a liquid at room temperature
- C. Oxidation of methyl alcohol can produce formaldehyde
- D. Dry distillation of calcium formate can produce formaldehyde:
Explanation: This is incorrect. Formaldehyde is a gas at room temperature.
Correct answer: Formaldehyde is a liquid at room temperature577. Formalin is
- A. 10% solution of formaldehyde in water
- B. 20% solution of formaldehyde in water
- C. 40% solution of formaldehyde in water
- D. 60% solution of formaldehyde in water
Explanation: Correct: Formalin is a 40% aqueous solution of formaldehyde
Correct answer: 40% solution of formaldehyde in water- A. Formic acid
- B. Formaldehyde
- C. Furfuraldehyde
- D. Acetone
Explanation: Formalin is a aqueous solution consisting of about 40% formaldehyde.
Correct answer: Formaldehyde- A. CHCl3
- B. Cl3CCHO
- C. CHI4
- D. ClCH2CH2Cl
Explanation: This compound, also known as trichloroacetaldehyde or chloral hydrate, is the correct option.
Correct answer: Cl3CCHO- A. Alkylation of benzene
- B. Acylation of benzene
- C. Oxidation of benzene
- D. Halogenations of benzene
- E. ABoth A and B
Explanation: Since the acyl group is added to the benzene as a result of this reaction process we can say that it is an acylation of benzene.
Correct answer: Acylation of benzene