ECAT Pre Engineering Chemistry Chapter 21 MCQ Test With Answer

• Electrophilic addition A
• Electrophilic substitution B
• Free radical substitution C
• Nuclophilic addition D

Which one of the following in mainly responsible for depletion of ozone layer?

• Methane A
• Carbon dioxide B
• Water C
• chloroflurocarbons D

Gammexane is

• Chlorobenzene A
• Benzyl chloride B
• Brommobenzene C
• Benzene hexachloride D

Grignard's reagent on treatment with dry CO₂and HCI yields

• Ester A
• Alcohol B
• Carboxylic acid C
• Aldehyde D

1-Chlorobutane on reaction with alcoholic potash gives

• But 1-ene A
• Butan-1-ol B
• But-2-ene C
• Butan-2-ol D

The rate of E₁reaction depends upon

• The concentration of substrate A
• The concentration of nucleophile B
• THe concentration of substrate as well as nucleophile C
• None of the above D

Catalyst in the reaction ROH + SOCl₂-------> RCL+SO₂+HCl is:

• ZnCl₂ A
• Pyridine B
• H₂SO₄ C
• Either D

Reaction of ethylamine with chloroform in alcoholic KOH produces

• CH₃OH A
• CH₃NC B
• C₂H₅NC C
• C₂H₅CN 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

Alkyle magnesium halides are known as

• Simon-smith reagent A
• Tollen's reagent B
• Grignard's reagent C
• Barford's reagent D

Alcohol can be prepared from Grignard's reagent with an aldehyde: If we start with formaldehyde the product alcohol with be

• Primary A
• Secondary B
• Territory C
• Aromatic D

Which one of the following is not a nucleophile

• H₂O A
• H₂S B
• BF₃ C
• NH₃ D

Which of the following undergoes uncleophilic substitution exclusively by S_N1 mechanism?

• Benzyl chloride A
• Ethyl chloride B
• Chlorobenzene C
• Isopropyl choride D

Alkyl halides on treatment with Zn and HCI gives

• Alkanes A
• Alkenes B
• Alkynes C
• Alcohols D

Steps in SN , reactions are:

• One A
• Two B
• Three C
• Four D

In a primary alkyl halide, the halogen atom is attached to a carbon which is further attached to

• Only one carbon atom A
• Two carbon atoms B
• Three carbon atoms C
• one or no carbon atom D

When CO₂is made to react with ethyl magnesium iodide, followed by acid hydrolysis, the product formed is

• Propane A
• Propanoic acid B
• Propanal C
• Propanol D

The most reactive compound for electrophilic nitration will be

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

Grignard's reagent is

• Alkyl halide A
• Magnesium halide B
• Alkyl magnesium halide C
• Ethereal solution of an alkyl halide 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

When ethyl iodide and n-propyl iodide are allowed to react with sodium metal in ether, the number of alkanes that could be produced is

• Only one A
• Two alkanes B
• Three alkanes C
• Four alkanes D

When CO₂ is made to react with ethyl megnesium iodine, followed by hydrolysis, the product formed is:

• Propane A
• Propanoic acid B
• Propanal C
• Propanol D

When alkyl halide is heated with aqueous solution of ammonia at 100°C the major product is

• Primary amine A
• Secondary amine B
• Tertiary amine C
• Mixture of amines and salt D

Elimination bimolecular reactions usually obey

• First order kinetics A
• Second order kinetics B
• Third order kinetics C
• Zero order kinetics D

A carbon atom carrying a postitive charge and attached to three other atoms of groups is called

• Caronium ion A
• Carbanion B
• Oconium ion C
• Carba ion D

Hydrolysis of Grignard's reagent yields

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

Reduction of alkyl halides give

• Alkanes A
• Alkenes B
• Ketones C
• Ether D

C₆H₆Cl₆can be obtained from

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

Grignard reagent is prepared by the reaction of magnesium metal with alkyl halide in the presence of

• Alcohol A
• Water B
• Suephuric acid C
• Dry ether D

Which of the following reagent cannot be used for preparing alkyl chloride from alcohol?

• HCl + anhyd. Zncl₂ A
• NaCl B
• PCl₅ C
• SOCl₂ D