ECAT Pre Engineering Chemistry Chapter 23 MCQ Test With Answer

Which compound would undergo nucleophilic addition

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

In 1903 Arthur Lapeworth became the first chemist to investigate a reaction mechanism. The reaction he investigated was that of hydrogen cyanide with propanone. What do we now call the mechanism of this reaction

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

Formalin is an aqueous solution of

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

The base used in Cannizzaro's reaction is

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

The carbon atom of a carbonyl group is

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

Hydrogenation of bezoyl chloride in presence of Pd on BaSO₄gives

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

Which one of the following statement is wrong regarding differences between aldehydes and ketones

• Aldehydes undergo reduction to form primary alcohols while ketones undergo reduction to form secondary alcohols A
• Aldehydes undergo oxidation to form acids having less number of carbon atoms while ketones undergo oxidation to form acids having same number of carbon atoms B
• Aldehydes give positive silver mirror test while ketones give negative -mirror test C
• Aldehydes can undergo polymerization while ketones cannot undergo polymerizarion D

The color of ppts formed by Fehling's test is

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

Chromic acid used to oxidize

• Aldehyde A
• Ketone B
• Both a and b C
• None of these D

Aldehydes can be distinguished from ketones by using

• Schiff's reagent A
• Conc. H₂SO₄ B
• Anhy. ZnCl₂ C
• Resorcinol D

Which isomer of C₅H₁₁OH gives, one dehydration, the greastest number of different alkenes

• 
  A
• 
  B
• 
  C
• 
  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

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

When vapours of isopropyl alcohol are passed over heated copper, the major product obtained is

• Propane A
• Propylene B
• Acetaldehyde C
• Acetone 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

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 one of the following is a product of the reaction between C₆H₅CH₂OH and CH₃COCI

• C₆H₅OCOCH₃ A
• C₆H₅CH₂CI B
• C₆H₅CH₂OCOCH₃ C
• C₆H₅CH₂COCI D

Self condensation of acetaldehyde in the presence of dilute alkalies gives

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

In formadaldehyde and KOH are heated then we get

• Acetylene A
• Methane B
• Methyl alcohol C
• Ethyl formate D

In carboxyl group the bond between C and oxygen is:

• Sigma bond A
• Single bond B
• Double Bond C
• Triple bond 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

Aniline reacts with which of these to form Schiff base?

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

Reaction of Grignard's reagent with formaldehyde gives:

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

Aldehydes are reduced to :

• Pri-alcohol A
• Sec-alcohol B
• Ter-alcohol C
• All of these D

Wacker method involves the conversion of alkene using PdCl₂into corresponding

• Alcohol A
• Ketone B
• Aldehyde C
• Ether 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

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

Acetaldehyde is used to make

• Rubbber A
• Antiseptics B
• Phenolic resin C
• All of these D