MCQs Of Haloalkanes And Haloarenes, Past Year Questions JEE Mains, Class 12, Chemistry


18 Questions MCQ Test Class 12 Chemistry 35 Years JEE Mains &Advance Past yr Paper | MCQs Of Haloalkanes And Haloarenes, Past Year Questions JEE Mains, Class 12, Chemistry


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This mock test of MCQs Of Haloalkanes And Haloarenes, Past Year Questions JEE Mains, Class 12, Chemistry for JEE helps you for every JEE entrance exam. This contains 18 Multiple Choice Questions for JEE MCQs Of Haloalkanes And Haloarenes, Past Year Questions JEE Mains, Class 12, Chemistry (mcq) to study with solutions a complete question bank. The solved questions answers in this MCQs Of Haloalkanes And Haloarenes, Past Year Questions JEE Mains, Class 12, Chemistry quiz give you a good mix of easy questions and tough questions. JEE students definitely take this MCQs Of Haloalkanes And Haloarenes, Past Year Questions JEE Mains, Class 12, Chemistry exercise for a better result in the exam. You can find other MCQs Of Haloalkanes And Haloarenes, Past Year Questions JEE Mains, Class 12, Chemistry extra questions, long questions & short questions for JEE on EduRev as well by searching above.
QUESTION: 1

Bottles containing C6H5I and C6H5CH2I lost their originallabels. They were labelled A and B for testing. A and B wereseparately taken in test tubes and boiled with NaOH solution.The end solution in each tube was made acidic with dilute HNO3 and then some AgNO3 solution was added. Substance B gave a yellow precipitate. Which one of the followingstatements is true for this experiment ? [2003]

Solution:

Since benzyl iodide gives yellow ppt. hence this is compound B and A was phenyl iodide (C6H5I).

QUESTION: 2

The compound formed on heating chlorobenzene withchloral in the presence of concentrated sulphuric acid, is   [2004]

Solution:

DDT is prepared by heating chlorbenzene and chloral with concentrated sulphuric acid

QUESTION: 3

Tertiary alkyl halides are practically inert to substitution bySN2 mechanism because of [2005]

Solution:

In an SN2 reaction, in the transition state, there will be five groups attached to the carbon atom at which reaction occurs. 

Thus there will be crowding in the transition state, and presence of bulky groups make the reaction sterically hindered.

QUESTION: 4

Alkyl halides react with dialkyl copper reagents to give                 [2005]

Solution:

In Corey House synthesis of alkanes alkyl halide react with lithium dialkyl cuprate

R'X + LiR 2Cu → R'-R + RCu + LiX

QUESTION: 5

Elimination of bromine from 2-bromobutane results in theformation of –            [2005]

Solution:

The formation of 2-butene is in accordance to
Saytzeff’s rule. The more substituted alkene is formed. 

QUESTION: 6

Phenyl magnesium bromide reacts with methanol to give   [2006]

Solution:

CH3OH + C6H5MgBr → CH3O.MgBr + C6H6

QUESTION: 7

Fluorobenzene (C6H5F) can be synthesized in the laboratory        [2006]

Solution:

        

QUESTION: 8

Reaction of trans 2-phenyl-1-bromocyclopentane onreaction with alcoholic KOH produces [2006]

Solution:


When the two groups to be eliminated are trans and lie in one plane with the two carbon atoms to which they are attached i.e. E2 reactions are stereoselectively trans.

QUESTION: 9

The structure of the major product formed in the following reaction 

 is

Solution:

QUESTION: 10

Which of the following is the correct order of decreasingSN2 reactivity?        [2007]

(X is a halogen)

Solution:

In SN2 mechanism transition state is pentavelent. For bulky alkyl group it will have sterical hinderance and smaller alkyl group will favour the SN2 mechanism. So the decreasing order of reactivity of alkyl halides is
RCH2X > R2CHX > R3CX

QUESTION: 11

The organic chloro compound, which shows completesterochemical inversion during a SN2 reaction, is [2008]

Solution:

SN2 reaction is favoured by small groups on the carbon atom attached to halogen.
So, the order of reactivity is
CH3Cl > (CH3)2CHCl > (CH3)3CCl > (C2H5)2CHCl

NOTE : SN2 reaction is shown to maximum extent by primary halides. The only primary halides given is CH3Cl. so the correct answer is (d).

QUESTION: 12

Consider the following bromides :

The correct order of SN1 reactivity is [2010]

Solution:

 

 

Since SN1 reactions involve the formation of
carbocation as intermediate in the rate determining step, more is the stability of carbocation higher will be reactivity of alkyl halides towards SN1 route. Now we
know that stability of carbocations follows the order :
3° > 2° > 1°, so SN1 reactivity should also follow the same order.
3° > 2° > 1° > Methyl (SN1 reactivity)

QUESTION: 13

How many chiral compounds are possible onmonochlorination of 2- methyl butane ? [2012]

Solution:

Four monochloro derivatives are chiral

QUESTION: 14

What is DDT among the following ? [2012]

Solution:

DDT is a non-biodegradable pollutant.

QUESTION: 15

CompoundCompound (A), C8H9Br, gives a white precipitate when warmed with alcoholic AgNO3. Oxidation of (A) gives an
acid (B), C8H6O4. (B) easily forms anhydride on heating. Identify the compound (A). [JEE M 2013]

Solution:

QUESTION: 16

In SN2 reactions, the correct order of reactivity for thefollowing compounds: [JEE M 2014]
CH3Cl,CH3CH2Cl, (CH3)2CHCl and ( CH3)3 CCl is:

Solution:

Steric congestion around the carbon atom undergoing the inversion process will slow down the SN2 reaction,
hence less congestion faster will the reaction. So, the order is
CH3Cl > (CH3)CH2 – Cl > (CH3)2CH – Cl > (CH3)3CCl

QUESTION: 17

The major organic compound formed by the reaction of 1, 1, 1-trichloroethane with silver powder is: [JEE M 2014]

Solution:

QUESTION: 18

The synthesis of alkyl fluorides is best accomplished by :        [JEE M 2015]

Solution:

Alkyl fluorides are more conveniently prepared by heating suitable chloro – or bromo-alkanes with organic fluorides such as AsF3, SbF3, CoF2, AgF, Hg2F2 etc.
This reaction is called Swarts reaction.
CH3Br + AgF → CH3F + AgBr
2CH3CH2Cl + Hg2F2 →2CH3CH2F + Hg2Cl2