ECAT Pre Engineering Chemistry Chapter 23 MCQ Test With Answer

Which reaction is of condensation or addition elimination reaction?

• Ketol A
• Aldol B
• Cannizzaro C
• All of these D

Aldehydes are produce in atmosphere by

• Oxidation of secondary alcohols A
• Reduction of alkenes B
• Reaction of oxygen atoms with hydrocarbons C
• Reaction of oxygen atoms with ozone D

Which reagent could be used to distinguish between CH₃CH(OH)CH₂CHO and CH₃COCH₂CH₂OH

• Acidified potassium dichromate A
• Dilute sulphuric acid B
• 2,4-dinitrophenylydrazine C
• Fehling's reagent D

Which reagent will distinguish a ketone from an aldehyde

• Br₂ A
• 2, 4-dinitrophenylhydrazine B
• NaBH₄ C
• Tollen's reagent D

On adding sodium nitroprusside ketones give

• Red A
• Wine red B
• White C
• Orange D

The catalytic prmoter used for the industrial preparation of acetaldehyde is

• PdCI₂ A
• CuCI₂ B
• Pd + CaCI₂ C
• None of these D

Which of the following gives iodoform on heating with a solution of I₂containing Na₂CO₃?

• Ethyl alcohol A
• Acetone B
• Ethyl alcohol as well as acetone C
• Methyl alcohol D

• Q and R Q and R A
• R only Q and R B
• Q and R R only C
• Q only R only D

What is formed when propanone is refluxed with an anhydrous solution of NaBH₄

• Propanal A
• Propan-1-ol B
• Propan-2-ol C
• Propane D

Which of the following will have the highest boiling point

• Methanol A
• Ethanol B
• Propanal C
• 2-hexanone D

On heating acetaldehyde with ammonical silver nitrate solution, we get

• CH₃OH A
• Silver acetate B
• HCHO C
• Silver mirror D

Acetal is produced by reacting alcohol in the presence of dry HCl with

• Acetaldehyde A
• Ketone B
• Ether C
• Carboxylic acid D

Hydrogenation of bezoyl chloride in presence of Pd on BaSO₄gives

• Benzyl alcohol A
• Benzaldehyde B
• Benzoic acid C
• Phenol D

Reaction of Grignard's reagent eith aldehyds other formaldehyde gives: Reaction of Grignard's reagent with formaldehyde gives:

• Pri-alcohol A
• Sec-alcohol B
• Ter-alcohol C
• Carboxylic D

During the mechanism of aldol condensation a/an ______ is formed

• Oxide A
• Alkali B
• Alkoxide ion C
• None of these D

Which alcohol may be oxidised to a product which react with 2,4-dinitorphenylhydrazine reagent but not with Fehling's reagent

• Butan-1-ol A
• Butan-2-ol B
• 2-methylpropan-1-ol C
• 2-methylpropan-2-ol D

Which of the following is halo form

• CHBr₃ A
• CHCI₃ B
• CHI₃ C
• All of these D

Which of the following compounds gives a ketone with Grignard's reagent?

• Formaldehyde A
• Ethanenitrile B
• Ethyl alcohol C
• Methyl iodide D

For which one of the following pairs of compounds can the members be distinguished by means of Tollen's test

• HCHO and CH₃CHO A
• CH₃CHO and CH₃COCH B
• CH₃COCH₃and C₆H₅COCH₃ C
• CH₃COOH and CH₃COOCH₃ D

At room temperature formaldehyde is

• Gas A
• Liquid B
• Solid C
• None of the above D

Aldehydes are oxidizes are to give:

• Primary alcohol A
• Sec-alcohol B
• Ter-alcohol C
• Carboxylic acid D

Which of the following does not react with phenyl hydrazine?

• Ethanol A
• Ethanal B
• Acetone C
• Acetophenone D

Condensation of aldeydes withα-hydrogen gives:

• Acetal A
• Ketal B
• Aldol C
• Cannizzaro product D

Formalin is an aqueous solution of

• Furfural A
• Fluorescein B
• Formaldehyde C
• Formic acid D

Wolf-kishner reduction is used for the reduction of

• Nitro compounds A
• Carboxylic acids B
• Carbonyl compounds C
• Olefins D

The color of ppts formed by Benedirct's test is

• Brick red A
• Wine red B
• Yellow C
• Orange D

Compounds X, Y and Z, all react with PCI₅to release hydrogen chloride, but only one of them reacts eith 2,4-dinitrophenylhydrazine reagent. Which one of the following combinations could be X, Y and Z

• 
  A
• 
  B
• 
  C
• 
  D

The base used in Cannizzaro's reaction is

• NaOH A
• KOH B
• CHI₃ C
• All of these D

Acetone reacts with HCN to form a cyanohydrin. It is an example of:

• Nucleophilic substitution A
• Nucleophilic addition B
• Electrophilic addition C
• Electrophilic substitution D

Acetone is oxidized with

• Tollen's reagent A
• Fehling solution B
• Acidic dichromate solution C
• Benedicts solution D