ECAT Pre Engineering Chemistry Chapter 23 MCQ Test With Answer

Dehydration of allcohol gives:

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

Which of the following will have the highest boiling point

• Methanol A
• Ethanol B
• Propanal C
• 2-hexanone 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 of the following is a method of converting a unsaturated ketone into unsaturated hydrocarbon?

• Aldol condensation A
• Reimer Tiemann reaction B
• Cannizaaor's reaction C
• Wolf-kishner reduction D

Which compound on reaction with hydrogen cyanide produces a compound with a chiral centre

• Ch₃CHO A
• CH₃CH₂COCH₂CH₃ B
• CH₃CO₂CH₃ C
• HCHO D

The catalytic prmoter used for the industrial preparation of acetaldehyde is

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

Aldelydes are the oxidation product of

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

Formaldehyde is used to make

• Plastics A
• Medicine B
• Antiseptic C
• All 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

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

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

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

• Propane A
• Propylene B
• Acetaldehyde C
• Acetone D

Which of the following reagents is used to distinguish acetone and acetophenone

• NaHSO₃ A
• Grinard reagent B
• Na₂SO₄ C
• NH₄Cl 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

Aniline reacts with which of these to form Schiff base?

• Acetic acid A
• Bezaldehyde B
• Acetone C
• NH₃ 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 an aqueous solution of

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

From which of the following tertiary butyl alcohol is obtained by the action of methyl magnesium iodide?

• HCHO A
• CH₃CHO B
• CH₃COCH₃ C
• CO₂ D

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

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

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

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

Which is mild oxidizing agent ?

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

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

Ethanal may be converted into a three-carbon acid in a two-step process.

Which compound is the intermediate

• CH₃CO₂H A
• CH₃CN B
• CH₃CH₂CN C
• CH₃CH(OH)CN D

Ketones are reduced to

• Primary alcohol A
• Secondary alcohol B
• Tertiary alcohol 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

Give IUPAC name fo Acetone

• Ethanal A
• Propanone B
• Butanone C
• Propanal D

The carbon of a carbonyl group is:

• sp hybridized A
• sp² hybridized B
• sp³ Hybidized 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 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

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