ECAT Pre Engineering Chemistry Chapter 21 MCQ Test With Answer

Action of Zn with alkyl halides in the presence of an inert solvent forms higher alkanes. This reaction is known as

• Wurtz reaction A
• Frankland's reaction B
• Cannizaro reaction C
• Kalobe's reaction D

Hydrolysis of Grignard's reagent yields

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

For which mechanisms, the first step involved is the same:

• E₁ and E₂ A
• E₂and SN₂ B
• E₂ and E₁ C
• E1 and SN₁ D

• Electrophilic substitution A
• Free radical reduction B
• Isomerisation C
• Nucleophilic substitution D

Alkyl halides are reactive :

• High A
• Medium B
• Less C
• Least D

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

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

Grignard's reagent on treatment with chloramine give

• Acetamide A
• Primary amice B
• Secondary amice C
• Urea D

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

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

Which of the following compounds will form a hydrocarbon on reaction with Grignard reagent

• A ketone A
• An aldehyde B
• An ether C
• Water D

When primary amine reacts with chloroform in ethanolic KOH, then the product is

• An isocyanide A
• An aldehyde B
• A cyanide C
• An alcohol D

The alkyl halide molecule on which a nucleophile attacks is called

• Substrate A
• Subsituent B
• Substituted C
• All of these D

Most reactive halide towards S_N1 reaction is

• n-Butyl chloride A
• sec-Butyl chloride B
• tert-Butyl choride C
• Allyl chloride D

Which of the followings is not a nulceophile

• OH^- A
• NH₃ B
• C₂H₅O^- C
• Br₂ D

Which of the following chlorocompounds is heat easily hydrolysed by hydorxide ion to give the product indicated

• 
  A
• 
  B
• 
  C
• 
  D

Butanenitrile is formed by reaction of KCN with

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

DDT is formed from

• Benzene and Chlorobenzene A
• Chloral and Chlorobenzene B
• Chloral and Benzene C
• Chlorobenzene and chlorine D

Reactivity of alkyl halides with magnisium is of the order:

• Rl > RBr> RCl > RF A
• RBr > RCl >RF > Rl B
• RCL > RF > Rl > RBr C
• RF >RI >RBr > RII D

Which is a weak nucleophile

• OH^- A
• Br^- B
• NH₃ C
• CI^- D

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

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

What happens when CCl₄is treated with AgNO₃solution?

• NO₂will be evolved A
• A white ppt. of AgCl will form B
• CCl₄will dissolve in AgNO₃solution C
• Nothing will happen D

SN₂ reaction has order of reaction :

• First A
• Second B
• Third C
• Zero 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

Alkyl halides ae considered to be very reactive compounds towards nucleophiles because

• They have an electrophilic carbon A
• They have an electrophilic carbon and a good leaving group B
• They have an electrophilic carbon and a bad leaving group C
• They have a nucleophilic carbon and a good leaving group D

Which of the following with aqueous KOH will give acetaldehyde?

• 1, 2-Dichloroethane A
• 1,1-Dichloroethane B
• Chloracetic acid C
• Ethyl chloride D

Thre rate of S_N2 reaction depends upon the

• Concentration of alkyl halides A
• Concentration of nucleophile B
• Concentration of alkyl halides and nucleophile C
• None of the above D

Elimination bimolecular reactions usually obey

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

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

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

Iodoethane reacts with sodium in ether, the product formed is

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

When formaldehyde is added to Grignard reagent we get

• Aldehyde A
• Acetone B
• Primary alcohol C
• Secondary alcohol D

The elimination of hydrogen halide from adjacent carbon atoms is called

• Dehydrogenation A
• Hydrogenation B
• Dehydrohalogenation C
• Hydrohalogenation D