ECAT Pre Engineering Chemistry Chapter 21 MCQ Test With Answer

E₂has molecularity :

• One A
• Two B
• Three C
• Half D

Among the following the most reactive towards alcoholic KOH is

• CH₂= CHBr A
• CH₃COCH₂CH₂Br B
• CH₃CH₂Br C
• CH₃CH₂CH₂Br D

C₆H₆Cl₆can be obtained from

• HCl and Benzene A
• Cl₂and Benzene and AlCl₃ B
• Cl₂and Benzene in diffused light C
• NaOCl and Benzene D

The general formula of alkyl halides is

• C_nH_2nX A
• C_nH_2n-1X B
• C_nH_2n+1X C
• C_nH_2n-2X D

Which of the following compounds gives trichoromethane on distilling with bleaching power?

• Methanal A
• Phenol B
• Ethanol C
• methanol D

Reaction of Griganard's reagent with CO₂gives:

• Aldehyde A
• Pri-alcohol B
• Sec-alcohal C
• Carboxylic acid D

Which of the following reacts with chloroform and base to form phenyl isocynaide?

• Nitrobenzene A
• Phenol B
• Chlorobenzene C
• Aniline D

Cyanoform is ________ acid in nature than the chloroform. The missing word is

• Stronger A
• Weaker B
• Amphoteric C
• Neutral D

When an alcohol reacts with SOCI₂an alkyl halide is formed. What are two other products

• SO₂and HCI A
• SI₂and H₂O B
• HCI and H₂O C
• H₂S and HCI D

Metal used in the preparation of Grignard's reagent is:

• Ca A
• Na B
• Mg C
• Zn D

Which represents nucleophilic aromatic substitution reaction?

• Reaction of benzene with Cl₂in sunlight A
• Benzyl bromide hydrolysis with water B
• Reaction of NaOH with dintrofluoro benzene C
• Sulphonation of benzene D

The order of reactivity of an alkyl halide (R-X) for a particular alkyl group is

• Iodide > bromide > chloride A
• Chloride > bromide > iodide B
• Bromide > chloride > iodide C
• Bromide > iodide > chloride D

If ketone reacts with Grignard's reagent, it also produces alcohol, But it will be a

• primary alcohol A
• Secondary alcohol B
• Tertiary alcohol C
• Aromatic alcohol D

C- X bond is strong in

• CH₃Cl A
• CH₃Br B
• CH₃F C
• CH₃I D

Any other aldehyde except formaldehyde on reaction with Grignard's will produce

• Secondary alcohol A
• Primary alcohol B
• Tertiary alcohol C
• Aromatic alcohol D

Which reaction is example of nucleophilic substitution

• 
  A
• 
  B
• 
  C
• 
  D

CFCs undergo homolytic fission by uv light in the stratosphere which radical could result from this irradiations of CHCICF₂Cl.

• CHF Cl C FCl A
• CH Cl CF₂Cl B
• CHF CF₂Cl C
• C FCl CF₂Cl D

In which of the following reactions is the inorganic reagent acting as a nucleophile

• 
  A
• 
  B
• 
  C
• 
  D

Ammonia like water also reacts with Grignard's reagent to give

• Alkane A
• Alkene B
• Alkyne C
• Amide D

Which of the followings is not a nulceophile

• OH^- A
• NH₃ B
• C₂H₅O^- C
• Br₂ D

• NH₃ HCl A
• KCN in C₂H₅OH NaOH B
• KCN in C₂H₅OH HCl C
• HCN NaOH D

SN₂reactions can be best carried out with:

• Prl. alkyl halide A
• Sec. Alkyl halide B
• Ter. Alkyl halide C
• All of three D

When chloroform is boiled with NaOH, it gives

• Formic acid A
• Trihydroxymethane B
• Acetylene C
• Sodium formate D

Unpleasant smell of carbylamine is obtained when chloroform and alcoholic KOH are heated with

• Any aromatic amine A
• Any primary amine B
• Any amine C
• Any aliphatic amine D

Alkyl halides in which a halogen atom is bonded to that carbon atom which directly bonded with one hydrogen atom is called

• Primary alkyl halides A
• Secondary alkyl halides B
• Tertiary alkyl halides C
• Quaternary alkyl halides D

Hydrolysis of Grignard's reagent yields

• Alcohol A
• Aldyhyde B
• Ester C
• Alkane D

Iodoethane reacts with sodium in ether, the product formed is

• Pentene A
• Propyne B
• Butene C
• Butane D

E₁mechanism is generally shown by

• 1° - RX A
• 2° - RX B
• 3° - RX C
• None of these D

The most reactive compound for electrophilic nitration will be

• Benzyl chloride A
• Benzoic acid B
• Nitrobenzene C
• Chlorobenzene D

Butanenitrile is formed by reaction of KCN with

• Propyl alcohol A
• Butyl chloride B
• Butyl alcohol C
• Propyl Chloride D