ECAT Pre Engineering Chemistry Chapter 23 MCQ Test With Answer

Aniline reacts with which of these to form Schiff base?

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

In Tolten's best, the end product is ______ formed

• White ppts A
• Red ppts B
• Yellow ppts C
• Silver mirror D

Propyne on hydrolysis in presence of H₂SO₄and HgSO₄gives

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

Condensation of aldeydes withα-hydrogen gives:

• Acetal A
• Ketal B
• Aldol C
• Cannizzaro product 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 reagent will distinguish a ketone from an aldehyde

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

Iodoform test is given by:

• Formaldehyde and Higher ketones A
• Formaldehyde B
• Acetaldehyde and methyl ketones C
• Acetaldehyde D

In carboxyl group the bond between C and oxygen is:

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

Aldehydes are oxidizes are to give:

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

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

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

In formadaldehyde and KOH are heated then we get

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

A compound A has a molecular formula C₂Cl₃OH. It reduces Fehling solution and on oxidation produces a monocarboxylic acid B.A can also be obtained by the action of Cl₂on Ethanol. A is

• Chloral hydrate A
• CHCl₃ B
• CH₃Cl C
• Chloroacetic acid D

The color of ppts formed by Fehling's test is

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

The carbon atom of a carbonyl group is

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

Dehydration of allcohol gives:

• Alkane A
• Alkene B
• Aldehyde C
• ketone D

Which of the following in incorrect?

• FelCl₃is used in the detection of phenols A
• Fehling solution is used in the detection of glucose B
• Tollen's reagent is used in detection of unsaturation C
• NaHSO₃is used in the detection of carbonyl compounds D

Ketones are prepared by the oxidation of

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

• Br_2(aq) A
• 2, 4-dinitrophenylhydrazine B
• NaBH C
• Tollen's reagent 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

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

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

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

Which is mild oxidizing agent ?

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

Benzophenone can be converted into benzene using

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

A nucleophilic reagent will readily Attack

• Ethylene A
• Ethanal B
• Ethanol C
• Ethylamine D

Wolf-kishner reduction is used for the reduction of

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

Which reaction yields Bakelite?

• Urea with HCHO A
• Tetramethyl glycol with Hezamethylene diisocyanate B
• Phenol and HCHO C
• Ethylene glycol and Dimethylterephthalate D

Aldehydes is distinguished from ketones by using

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

Wacker method involves the conversion of alkene using PdCl₂into corresponding

• Alcohol A
• Ketone B
• Aldehyde C
• Ether 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

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