CBSE Questions for Class 12 Engineering Chemistry Haloalkanes And Haloarenes Quiz 2 - MCQExams.com

Ethyl iodide and n-propyl iodide are allowed to undergo Wurtz reaction. The alkane which will not be obtained in this reaction is:
  • butane
  • propane
  • pentane
  • hexane
The Major products obtained when this substance is subjected to $${ E }_{ 2 }$$ reaction will be:
1068143_36c8c5d90e3b41ca897e0429a4b96fc9.png
  • both $$1$$ and $$3$$
Given reaction is an example of Nucleophilic aromatic substitution. Which of the following halide $$(-X)$$ is most readily replaced.
995504_5f48574c6195497d892a3a25688eaeda.png
  • $$-F$$
  • $$-Cl$$
  • $$-Br$$
  • $$-I$$

$$CH_3 - \underset{CH_3\!\!\!\!\!}{\underset{|}{\overset{CH_3\!\!\!\!\!}{\overset{|}{C}}}} - Br \xrightarrow[\Delta]{KOH (alcoholic)} (A) \xrightarrow{HBr/R_2O_2} \underset{(Major)}{(B)}$$ Product $$B$$ is:
  • $$CH_3 - \underset{H}{\underset{|}{\overset{\,\,\,\,\,CH_3}{\overset{|}{C}}}} - CH_2 - Br$$
  • $$CH_3 - \underset{\,\,\,Br}{\underset{|}{\overset{\,\,\,\,\,CH_3}{\overset{|}{C}}}} - CH_3$$
  • $$CH_3 - \underset{\,\,\,\,\,\,\,\,\,\,\,CH_2 - Br}{\underset{|\,}{\overset{\,\,\,\,\,\,CH_3}{\overset{|\,}{C}}}} - OH$$
  • $$CH_3 - \underset{\,\,\,\,\,\,CH_3}{\underset{|}{\overset{\,\,\,\,\,\,\,\,\,\,\,\,CH_2 - H}{\overset{|}{C}}}}-Br$$
Find out the major product.
1092871_3cf7523e31d441b8900847e8f05b3bc2.png
The reaction of toluene with chlorine in the presence of light gives:
Which of the following alkyl halides will undergo $$S_N1$$ reaction most readily?
  • $$(CH_3)_3C-F$$
  • $$(CH_3)_3C-Cl$$
  • $$(CH_3)_3C-Br$$
  • $$(CH_3)_3C-I$$
Product D in the reaction is:
1054666_44c9a26e06be42c28267d33d69d92aeb.png
  • optically active cyanide
  • optically inactive cyanide
  • optically active acid
  • optically active aldehyde
In which of the following reactions, it proceeds via free radical mechanism?
  • Halogenation of benzene
  • Nitration of benzene
  • Sulphonation of benzene
  • Chlorination of toluene at high temperature
But-2-yne on chlorination gives:
  • 1-chlorobutabe
  • 1,2-dichlorobutabe
  • 1,1,2,2-tetrachloro butane
  • 2,2,3,3-tetrachloro butane
The product of reaction between chloroform and ethylamine in presence of alcoholic $$KOH$$ is allowed to react with $$Cl_2$$.
The final product is:
  • ethyl chloride
  • ethylene dichloride
  • ethyl iminocarbonyl chloride
  • acetaldehyde
Which one of the following compound will be most reactive for $$S_N1$$ reaction ?
Which of the compound gives a mixture of the substitution products on reaction with $$NaNH_{2}$$ in liquid $$NH_{3}$$?
Correct order of $$S_N1$$ rate of the given compounds is:

1168458_422b667f80924268805244affe1bbbd4.png
  • $$I > II > III >IV$$
  • $$II > I > IV > III$$
  • $$I > IV > III > II$$
  • $$III > IV > I > II$$
Which of the following is most likely to show optical isomerism?
n-Propyl chloride and isopropyl chlordie mixture is subjected to the Wurtz reaction, which one of the following compounds is not formed.
  • Hexane
  • 2,5-Dimethyl hexane
  • 2,3-Dimethyl butane
  • 2-Methyl pentane
Which is most reactive for $$SN^{1}$$ reaction:-
The reaction of tertiary butyl bromide with sodium methoxide gives
  • Isobutane
  • Tertiary butyl methyl ether
  • Isobutylene
  • Butene
Identify the compound that give product on reaction with Zn dust and heat.
Which of the following compound give solvolysis reaction with slowest rate?
  • $$P-\overset { \oplus }{ N } { R }_{ 3 }-{ C }_{ 6 }{ H }_{ 4 }-C{ H }_{ 2 }-Br$$
  • $$P-CCl_{3}-C_{6}H_{4}-CH_{2}-Br$$
  • $$p-N$$$$\equiv C- $$$$C_{6}H_{4}-CH_{2}-Br$$
  • $$C_{6}H_{5}-CH_{2}-Br$$
Which of the following compounds are optically active ?
  • $$CH_3-CHOH-CH_2-CH_3$$
  • $$H_2C = CH-CH_2-CH=CH_2$$
Arrange the following in order of decreasing rate in an $$E_2$$ reaction
1177165_b137e98059014f5eb0e92e6dcb603e64.PNG
  • $$1 > 2 > 3$$
  • $$3 > 1 > 2$$
  • $$3 > 2 > 1$$
  • $$2 < 3 < 1$$
The major product of the following reaction is:


1179139_ba8f6d9ad7f14104bdd754f603ba55a3.png
Which of the these compounds represents the major monobromination isomer formed in the following reaction?
1196253_c0c58b69c2314a8cadd00f369a279786.png
Product (D) in the reaction is: 
1184045_b2da9ce26f254ebfa6d0121d867516b0.png
  • optically active cyanide
  • optically inactive acid
  • optically active acid
  • optically active aldehyde
The reagent used in dehydrohalogenation process is 
  • alcoholic KOH
  • $$NaNH_2$$
  • $$C_2H_5ONa$$
  • All of these
Which one of the following compound is most reactive towards $$SN^1$$ reaction
The IUPAC name of this compound is-
1246777_9fa1826b8f1b42e380840acfa76866cb.png
  • 2- Flouro-4-chloro-2,4-diethyl-1-pentane
  • 3-Flouro-5-chloro-3-methyl-5-ethyl-1-hexane
  • 3-Chloro-5-fluoro-3,5-dimethyl-1-heptane
  • 3,5-Dimethyl-5-fluoro-3-chloro-heptane
2-methylbut -3-en-2-ol reacts with $$HBr$$ and
  • Produces $$1^\circ$$ - Bromide as major product through $$S_N 1$$ mechanism
  • Produces $$3^\circ$$ - Bromide as major product through $$S_N 1$$ mechanism
  • Produces $$1^\circ$$ - Bromide as major product through $$S_N 2$$ mechanism
  • Produces $$3^\circ$$ - Bromide as major product through $$S_N 2$$ mechanism
Mark the true statement concerning mesomeric effect?
a) It occurs in system having conjugate double bonds in compounds
b) It involves electrons of $$\pi $$ bonds
c) The electron pair is transferred completely
d) It involeves lone pair of elctrons 
  • True
  • False
Identify 'Z' in the following reaction series , $$CH_{3}CH_{2}CH_{2}Br \xrightarrow {NaOH} (X) \xrightarrow [ \triangle] {Al_{2}O_{3}} (Y) \xrightarrow {HOCl} (Z) $$
Select the incorrect statement (s) 
  • $${{\text{S}}_{\text{N}}}{\text{1}}$$ reactions also take place with some elimination.
  • $${{\text{S}}_{\text{N}}}{\text{2}}$$ reactions with chiral compounds gives racemic mixture.
  • $${{\text{S}}_{\text{N}}}{\text{1}}$$ reactions is faster in more polar aprotic solvents.
  • All of the above are incorrect statements.
The herbicide 2,4-dichlorophenoxyacetic acid, generally called 2,4-D, is synthesized from 2,4-dichlorophenol and chloroacetic acid. The synthesis involves which of these reactions:
  • $$\rm{S_N1}$$
  • $$\rm{ArS_N}$$
  • $$\rm{S_N2}$$
  • $$\rm{S_Ni}$$
Which alcohol will give only $$E_{1}$$ reaction?
Identify the following species in which elimination of $$HBr$$ of two $$Br$$ atoms is stereoselective.
  • $$CH_{3}CH_{2}CHBr_{2}$$
  • $$CH_{3}CH_{2}CH_{2}Br$$
  • $$CH_{3}CH_{2}\underset{Br}{\underset{|}{CH}}CH_{2}$$
  • $$CH_{3}\underset{Br}{\underset{|}{CH}}\underset{Br}{\underset{|}{CH}}CH_{3}$$
Given the correct order of initial $$T$$ or $$F$$ for the following statements. Use $$T$$ if the statement is true and use $$F$$ if the statement is false.
I. $$Me-CH=C=C=CH-Br$$ is optically active.
II. All optically active compounds are chiral.
III. All chiral pyramidal molecules are optically inactive.
IV. $$CH_{3}-CH_{2}-CH_{2}-COOH$$ and $$CH_{3}-CH_2-CH_{3}$$ are positional isomers.
  • $$TTTF$$
  • $$FTFT$$
  • $$FTFF$$
  • $$TFTT$$
Which of the following compound may be optical active ?
  • $$Co{(en)_2}C{I_2}$$
  • $${\left[ {Rh{\rm{ CI Br N}}{{\rm{H}}_3}{\rm{ P}}{{\rm{H}}_3}} \right]^ - }$$
  • $$Cu{(en)_2}C{I_2}$$
  • All of these
Which of the following compound will rotate the plane polarized light at room temperature?
Alkyl halides can be obtained by all methods except?
  • $$CH_{3}-CH_{2}-CH_{3} + Cl_2 \xrightarrow [ UV\ light ]{ } $$
  • $$CH_{3}CH_{2}OH+HCl/ZnCl_{2}\rightarrow$$
  • $$C_{2}H_{5}OH+NaCl\rightarrow$$
  • $$CH_{3}COOAg+Br_{2}/CCl_{4}\rightarrow$$
Compound $$C_4H_8Cl_2 \,(A)$$ on hydrolysis gives a compound $$C_4H_8O(B)$$ which reacts with hydroxylamine and does not give any test with Tollens regent . What are (A) and (B)?
  • $$1,1-$$ Dichlorobutane and butanal
  • $$2,2-$$ Dichlorobutane and butanal
  • $$1,1-$$ Dicholorobutane and butan $$-2-$$ one
  • $$2,2-$$ Dichlorobutane and butan $$-2-$$ one
$$Compound (refer\ image)\overset { alc. }{ \underset { KOH }{ \longrightarrow  }  } (A)\overset { NBS }{ \longrightarrow  } (B)\overset { alc. }{ \underset { KOH }{ \longrightarrow  }  } (C)\overset { NBS }{ \longrightarrow  } (D)\overset { alc. }{ \underset { KOH }{ \longrightarrow  }  } (E)$$ The product E is 
1530046_51587c25c2ec4c7e8ad159dff1fc50d2.PNG
Provide the structure of the major organic product which results in the following reaction.
1532904_b85df8253cf34a23848968a1d6f106c4.png
Which one is not prepared by Wurtz reaction?
  • $$C_4H_8$$
  • $$CH_4$$
The major product of the following reaction is :

629569_3e527380fdba417588f34ee51673dee1.png
Choose the correct options (s) that gives (s) aromatic compound as the major product:
The compound $$C_{7}H_{8}$$ undergoes the following reactions:
$$C_{7}H_{8}\xrightarrow {3Cl_{2}/\triangle}A \xrightarrow {Br_{2}/ Fe} B \xrightarrow {Zn/HCl}C$$. The product $$C$$ is:
  • $$3-$$bromo$$-2,4,6-$$trichlorotoluene
  • $$m-$$bromotoluene
  • $$p-$$bromotoluene
  • $$o-$$bromotoluene
Among the following, the reaction that proceeds through an electrophilic substitution is:
In an $$S_N1$$ reaction on chiral centres, there is:
  • $$100$$% retention
  • $$100$$% inversion
  • $$100$$% racemization
  • Inversion more than retention leading to initial racemization
Which of the following is the most correct electron displacement for a nucleophilic reaction to take place?
Which of the following alkane cannot be made in good yield by Wurtz reaction? 
  • 2,3-Dimethylbutane
  • n-Heptane
  • n-Butane
  • n-Hexane
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