ECAT Pre Engineering Chemistry Chapter 23 MCQ Test With Answer

Aldehyde and small methyl ketones form crystalline ______ ppts with saturated sodium bisulphate solution

• White A
• Red B
• Yellow C
• None of these D

Which of the following is halo form

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

Which of the following will have the highest boiling point

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

Aldelydes are the oxidation product of

• P-alcohols A
• s-alcohols B
• ter-alcohols C
• carboxylic acids 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

Which of the following compounds will react with Tollen's reagent

• 
  A
• 
  B
• 
  C
• 
  D

A common industrial solvent is a mixture of propanone; CH₃COCH₃, and pentyl ethanoate CH₃CO₂(CH₂)₄CH₃. Which reagent would have no effect on this solvent

• Na_(s) A
• NaBH₄ B
• NaOH_(aq) C
• 2,4-dinitrophenylhydrazine reagent D

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

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

Cannizzaro's reaction in not given by

• Formaldehyde A
• Acetaldehyde B
• Benzaldyhyde C
• Trimethylacetaldehyde D

The carbon atom of a carbonyl group is

• Sp hybridized A
• Sp²hybridized B
• Sp³hybridized C
• None of these D

Aldehydes is distinguished from ketones by using

• Tollen's reagent A
• Benedict reagent B
• Fehling solution C
• All of the above D

The IUPAC name fo CH₃COCH (CH₃)₂is

• 4-Methylisopropyl ketone A
• 3-Methyl-2 butanone B
• Isopropylmethyl ketone C
• 2 - Methyl- 2 butanone D

Aldehydes which do not haveα-hydrogen undergo

• Aldol combination A
• Cannizzaro's reaction B
• Substitution C
• Elimination D

Reaction of Grignard's reagent with formaldehyde gives:

• pri-alcohol A
• sec-alcohol B
• ter-alcohol C
• carboxylic 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

• With H₂/Ni CH₃(CH₂)₅CH₂OH A
• With H₂/Ni CH₃(CH₂)₅CH₃ B
• With NaBH₄ CH₃(CH₂)₅CH₂OH C
• With NaBH₄ CH₃(CH₂)₅CHO D

Aldehydes are oxidizes are to give:

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

Which of the following compounds will react with reagent ?

• CH₃ CO H A
• CH₃ CO CH₃ B
• CH_{3 COOH} C
• CH₃ CO CH₂CH₃ D

Which is mild oxidizing agent ?

• Tollen's reagent A
• KMnO₄ / H₂SO₄ B
• K₂Cr₂O₇ / H₂SO₄ C
• HNO₃ D

Aldol condensation is actually

• Electrophilic addition of carbonation A
• Electrophilic addition of carbonium ion B
• Nucleophilic addition of carbonation C
• Nuclephilic addition of carbonium ion D

Aldehydes and ketones are carbonyl compounds. Which of them react both with NaBH₄and with Tollen's reagent

• Both aldehydes and ketones A
• Aldehydes only B
• Ketones only C
• Neither aldehydes nor ketones D

Chromyl chloride and toluene react to produce

• p-chlorotoluene A
• Benzaldehyde B
• Benzyl chloride C
• Bezoic acid D

Aldehydes can be distinguished from ketones by

• 2,4-DNPH test A
• NaHSO₃test B
• N₂H₄test C
• Tollen's test D

Propyne on hydrolysis in presence of H₂SO₄and HgSO₄gives

• Acetaldehyde A
• Acetone B
• Formaldehyde C
• None D

Self condensation of acetaldehyde in the presence of dilute alkalies gives

• An acetal A
• An aldol B
• Mesitylene C
• Propionaldehyde D

An organic compound has the following properties ; It gives a positive tri-iodomethane test; it gives a yellow ppt, with 2, 4-DNP regent; it does not react with Tollen's reagent . Which compound would give these results

• CH₃CHO A
• CH₃CH₂OH B
• CH₃CH₂COCH₃ C
• CH₃CH₂CH₂CHO D

Aromatic aldehydes undergo disproportionation in presence of sodium or potassium hydroxide to give corresponding alcohol and acid. The reaction is known as

• Wurtz reaction A
• Cannizzaro reaction B
• Friedel Craft reaction C
• Claisen reaction D

The homologous series of aldehydes and ketones have general formula:

• C_nH_2nO A
• C_nH_nO B
• C_nH_2n-1O C
• C_nH_nO_n D

Ketones are prepared by the oxidation of:

• Primary alcohol A
• Secondary alcohol B
• Tertiary alcohol C
• None of these 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