ECAT Pre Engineering Chemistry Chapter 23 MCQ Test With Answer

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

A food chemist wants to create the odour of pineapples for a product. An ester with this odour has the formula C₃H₇COOC₂H_5.Which pair of reagents would produce this ester

• C₂H₅CI and C₃H₇COOH A
• C₂H₅OH and C₃H₇CONH₂ B
• C₂H₅OH and C₃H₇COOH C
• C₃H₇OH and C₂H₅COCI D

Which of the following will have the highest boiling point

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

C₂H₅CHO and (CH₃)₂CO can be distunguished by testing with

• Phenyl hydrazine A
• Hydroxylamine B
• Fehling solution C
• Sodium bisulphate D

Which of the following react with NaOH to produce an acid and an alcohol?

• NCHO A
• CH₃COOH B
• CH₃CH₂COOH C
• C₆H₅COOH 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

The color of ppts formed by Fehling's test is

• Brick red A
• Red B
• Yellow C
• Orange 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

Aniline reacts with which of these to form Schiff base?

• Acetic acid A
• Bezaldehyde B
• Acetone C
• NH₃ D

Which of the following compounds will not give iodoform test on treatment with I₂/ NaOH?

• Acetaldehyde A
• Acetone B
• Butane C
• 3-pentanone D

• 2-chlorobutanal A
• alfa-chlorobutanal B
• 2-chlorobutyraldehyde C
• alfa- chlorobutyraldehyde D

Hydroxyl amine is a derivative of::

• Alcohol A
• Aldehyde B
• Ammonia C
• Ketone D

On heating acetaldehyde with ammonical silver nitrate solution, we get

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

Condensation of aldeydes withα-hydrogen gives:

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

Aldehydes are oxidizes are to give:

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

Benzophenone can be converted into benzene using

• Fused alkali A
• Anhydrous AlCl₃ B
• Sodium amalgam in water C
• Acidfied dichromate D

Which of the following organic compounds exhibits positive Fehling test as well as iodoform test?

• Methanal A
• Ethanol B
• Propanone C
• Ethanal D

Self condensation of acetaldehyde in the presence of dilute alkalies gives

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

Cyanohydrin of which of the following forms lactic acid

• HCHO A
• CH₃COCH₃ B
• CH₃CHO C
• CH₃CH₂CH₂CHO D

Which of the following alcohols cannot be produced by treatment of aldehydes or ketones with NaBH₄or LiAIH₄?

• 1-propanol A
• 2-propanol B
• 2-Methyl-2-propanol C
• Ethanol D

Which is mild oxidizing agent ?

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

Formaldehyde is used to make

• Plastics A
• Medicine B
• Antiseptic C
• All of these D

Cannizzaro's reaction in not given by

• Formaldehyde A
• Acetaldehyde B
• Benzaldyhyde C
• Trimethylacetaldehyde 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

In aldol condensation reaction, a double bond is formed between ______ and ______ carbon atoms

• αandβ A
• αandα B
• αand Y C
• None of these D

Ketones are prepared by the oxidation of:

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

Formalin is:

• 10% solution of formaldehyde in water A
• 20% solution of formaldehyde in water B
• 40% solution of formaldehyde in water C
• 60% solution of formaldehyde in water D

Which compound would undergo nucleophilic addition

• Ethene, C₂H₄ A
• Bromoethane, C₂H₅Br B
• Ethanal, CH₃CHO C
• Ethane, C₂H₆ D

Silver mirror test is applied for

• Aldehydes A
• Alcohols B
• Acids C
• Esters D