ECAT Pre Engineering Chemistry Chapter 23 MCQ Test With Answer

At room temperature formaldehyde is

• Gas A
• Liquid B
• Solid C
• None of the above D

Silver mirror test is applied for

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

Wacker method involves the conversion of alkene using PdCl₂into corresponding

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

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

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

The catalytic prmoter used for the industrial preparation of acetaldehyde is

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

Give IUPAC name fo Acetone

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

The base used in Cannizzaro's reaction is

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

Propyne on hydrolysis in presence of H₂SO₄and HgSO₄gives

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

Acetone is prepared by

• Oxidation of n-propyl alcohol A
• Oxidation of acetaldehyde B
• Pyrolysis of calcium acetate C
• Pyrolysis of calcium acetate as well as acetic acid D

Which of the following reagent will react with both aldehyde and ketones?

• Grinard's reagent A
• Tollen's reagent B
• Fehling's reagent C
• Benedict's reagent D

In which reaction, aromatic aldehyde is treated with acid anhydride in the presence of corresponding salt of the acid to give unsaturated aromatic acid?

• Friedel-Crafts reaction A
• Perkin's reaction B
• Wurtz reaction C
• None of these D

A nucleophilic reagent will readily Attack

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

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

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

Which of the following is hypnotic?

• Acetaldehyde A
• Metaldehyde B
• Paraldehyde C
• None D

Ketones are prepared by the oxidation of:

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

The color of ppts formed by Fehling's test is

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

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

Which of the following reactions is used for detecting presence of carbonyl group?

• Reaction with hydroxylamine A
• Reaction with hydrazine B
• Reaction with phenyl hydrazine C
• All 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 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

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

• 
  A
• 
  B
• 
  C
• 
  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

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 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

Carboxyl compounds have functional group:

• R-C-X A
• R-CH=O B
• RCOR C
• All D

Ketones are reduced to

• Primary alcohol A
• Secondary alcohol B
• Tertiary alcohol C
• All of these 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