CBSE Questions for Class 12 Engineering Chemistry Haloalkanes And Haloarenes Quiz 11 - MCQExams.com

$$A + Na/\Delta  \rightarrow$$ no gaseous product
$$A + Br_2/FeBr_3  \rightarrow C_7H_7OBr$$ (two isomers).
Based on the above reactions, identify A from the given options.
The alkene limonene has following structure, (Ref. image). Which product results from the reaction of Limonene and $$1$$ molar equivalent chlorine water?

117488_e0d94bab59f8489fab41f8c335f6a0d7.png
Action of alcoholic $$AgNO_3$$ on chlorobenzene is similar to the action on:
  • allyl chloride
  • vinyl chloride
  • isopropyl chloride
  • benzyl chloride
Correct statement (s) about reaction & related graph is (are):
127888_ba96f3344bda4ccd8a284c20f9332743.png
  • P & Q are nucleophilic substitution products by $$S_{N}2$$ reaction mechanism
  • only R & S are elimination products by $$E2$$ reaction mechanism
  • P is nucleophilic substitution product by $$S_{N}2$$ reaction mechanism
  • Q, R, S are elimination products by $$E_2$$ reaction mechanism
 Which of the following is fast debrominated?
127826.png
  • IV
  • II
  • III
  • I
$$Ph-CH=CH_{2}+BrCCl_{3}\xrightarrow{peroxide} $$
Product is :
Which alkyl halide undergo $$E_{2}$$ elimination?
In which of the following cases, configuration about chiral $$C^*$$ is retained?
An aromatic compound $$\displaystyle 'A' (C_{7}H_{6}Cl_{2}$$), gives $$AgCl$$ on boiling with alcoholic $$AgNO_3$$ solution, and yields $$\displaystyle C_{7}H_{7}OCl$$ on treatment with sodium hydroxide. 'A' on oxidation gives a mono chlorobenzoic acid which affords only one mononitro derivative. The compound A is :
$$CH_3-\!\!\overset{\,\,CH_3}{\overset{|}{\underset{\,\,\,CH_3}{\underset{|}{C}}}\!\!\!-}\,CH=CH_2\xrightarrow{dil.H_2SO_4}\,\,\xrightarrow[\Delta]{conc.H_3PO_4}\,\,\xrightarrow[(ii)\, Zn / H_2O]{(i)\, O_3}$$
Final product is / are:
  • $$\underset{CH_3}{\underset{|}{C}=}\,O$$

  • $$HCHO + CH_3-\overset{O}{\overset{||}{C}}-\underset{CH_3}{\underset{|}{C}H}-CH_3$$
  • $$CH_3CHO +$$ $$CH_3-\overset{O}{\overset{||}{C}}-CH_3$$
  • $$CH_{3}CHO+HCHO$$
Suppose the double bonded methylene group of $$1$$-bromo-$$2$$-propene is labelled with $$_{  }^{ 13 }{ C },{ H }_{ 2 }{  }^{ 13 }{ C }=CH-{ CH }_{ 2 }Br$$. What product will be formed by methanolysis of this substrate?
  • $${ H }_{ 2 }{ }^{ 13 }{ C }=CH-{ CH }_{ 2 }-O{ CH }_{ 3 }$$ and $${ H }_{ 2 }C=CH-_{ }^{ 13 }{ { CH } }-O{ CH }_{ 3 }$$
  • $${ H }_{ 2 }C=_{ }^{ 13 }{ { CH } }-{ CH }_{ 2 }-O{ CH }_{ 3 }$$
  • $${ H }_{ 2 }{ }^{ 13 }{ { C } }=CH-{ CH }_{ 2 }-O{ CH }_{ 3 }$$
  • $${ H }_{ 2 }C=CH-_{ }^{ 13 }{ { CH }_{ 2 } }-O{ CH }_{ 3 }$$
Select correct statement about  the product (P) of the reaction:
128916.png
  • P is optically inactive due to internal compensation
  • P is optically inactive due to the presence of plane of symmetry in the molecule
  • The structure of P can have three optical isomers possible.
  • P can have four possible optical isomers.
In an Aprotic solvent, which relative ordering best describes the nucleophilicity of the halide ions?
  • Iodide> Bromide> Chloride>> Flouride
  • Iodide> Bromide> Chloride> Flouride
  • Iodide< Bromide< Chloride< Flouride
  • Iodide< Bromide> Chloride> Flouride
What is the best term to describe the rearrangement that causes the conversion of $$3$$-bromo-$$2,2$$-dimethylbutane to $$2,3$$-dimethyl-$$2$$-butanol?
  • $$1,2$$-methyl shift
  • $$1,3$$- hydride shift
  • $$1,3$$-methyl shift
  • $$1,2$$- hydride shift
In the following pair of compounds, which of the following relation is correct for nucleophilicity in a polar-protic solvent?

  • $${ CH }_{ 3 }S{ CH }_{ 3 } >{ CH }_{ 3 }O{ CH }_{ 3 }$$
  • $${ CH }_{ 3 }S{ CH }_{ 3 } <{ CH }_{ 3 }O{ CH }_{ 3 }$$
  • $${ CH }_{ 3 }S{ CH }_{ 3 } ={ CH }_{ 3 }O{ CH }_{ 3 }$$
  • None of these
Which of the given pair of $${ S }_{ N }1$$ reaction would you expect to proceed faster? 

141350.png
  • $$HBr > NaBr $$
  • $$HBr < NaBr $$
  • $$HBr = NaBr $$
  • None of these
Which alkene is formed as the major product in the $$E_2$$ reaction of the given compound?

137342_41485ad5cd914c668ea5423fe3a9a2e5.png
  • $$3$$-methylcyclonex-($$1$$)-ene
  • $$1$$-deutero-$$3$$-methylcyclohex-($$1$$)-ene
  • $$1$$-methyl-$$3$$-deuterocyclohex-(1)ene
  • both A and B
The most stable carbocation formed on debromination is :
Explain the relative rate of $$E2$$ reaction of the given compounds.

141711.png
  • $$ III < I < II $$
  • $$ I < II < III $$
  • $$ III < II < I $$
  • None of these
$$CH{Cl}_{3}$$ does not give white ppt. with $$Ag{NO}_{3}$$ because it:
  • is a covalent compound
  • does not give $$Cl$$ ions in solution
  • is not dissociated in water
  • none of the above
Which of the following will give $$S_N$$ reaction?
  • $$R-Br$$
  • $$R-{N}_{3}$$
  • $$R-\overset { \oplus }{ { OH }_{ 2 } } $$
  • All
Compound $$(A)$$ on reaction with $${NH}_{2}{NH}_{2}+OH$$ gives:
250420.PNG
Which of the following gives $${S_N}{1}$$ reaction?
  • $$MeBr$$
  • All
For the reaction given, which substrate will give maximum racemisation?
250885.PNG
$$\beta$$-Elimination or anti-elimination reaction is carried out with base $$({ B }^{ \overset { .. }{ \ominus  }  })$$ as shown.
The following bases are used.
$$(I) \overset { \ominus \quad  }{ OH } $$  $$(II) R{ O }^{ \ominus  }$$  $$(III) RCO{ O }^{ \ominus  }$$  $$(IV) \overset { \ominus  }{ C } N$$  $$(V) N{ O }_{ 3 }^{ \ominus  }$$
The decreasing order of reactivity for the above elimination is :
251263_f1e49f0d076c484e85176c1de4414169.png
  • $$(II)>(I)>(IV)>(III)>(V)$$
  • $$(V)>(III)>(IV)>(I)>(II)$$
  • $$(II)>(I)>(III)>(IV)>(V)$$
  • $$(I)>(II)>(III)>(IV)>(V)$$
Fugacity power of which group will be maximum?
  • $${ CH }_{ 3 }-O-\overset { O\\ \parallel }{ \underset { \parallel \\ O }{ S } } -{ C }_{ 2 }{ H }_{ 5 }$$
  • $${ CH }_{ 3 }-O-\overset { O\\ \parallel }{ \underset { \parallel \\ O }{ S } } -{ CH }_{ 3 }$$
  • $${ CH }_{ 3 }-O-\overset { O\\ \parallel }{ C } -{ CH }_{ 3 }$$
In Dow's process for the manufacture of phenol, $$PhCl$$ is fused with $$NaOH$$ at elevated temperature under pressure.
$$PhCl\xrightarrow [ 623K,300atm ]{ NaOH } \left[ Intermediate \right] \xrightarrow [  ]{ { H }_{ 2 }O } \underset { (A)+(B+C)\\ side\ product }{ Phenol } $$
Which of the following statements are correct?
  • Phenol is formed via the formation of benzyne intermediate
  • p-phenyl phenol is also formed as a by-product
  • Diphenylether is also formed as a by-product
  • Biphenylene is also formed as a by-product
Which of the following give $${S_N}{1}$$ reaction?
Select the correct answer.
250882.PNG
  • $$(I),(II)$$ and $$(III)$$
  • $$(I)$$ and $$(II)$$
  • $$(II),(III)$$ and $$(IV)$$
  • $$(I),(III)$$ and $$(IV)$$
In the given reactions, the rate of reaction of $$(I)$$ and $$(II)$$ are same. Both reactions proceed by which mechanism?
253039_afc50257f4ca4d7cbb1c44c32188b202.png
  • $$E_1$$
  • $$E_2$$
  • $$E_1cb$$
  • Anti-elimination
Which of the following statements are correct about the following reactions?
252268_b888c45d79c645999c4a722d2b584542.png
  • Reaction $$1$$ proceeds by $${S_N}{2}$$ and reaction $$2$$ by $${S_N}{1}$$ mechanism
  • Reaction $$1$$ proceeds by $${S_N}{1}$$ and reaction $$2$$ by $${S_N}{2}$$ mechanism
  • (B)$$\Rightarrow$$(-) $$Ph-\overset{OH}{\overset{|}CH}-CH=CH-Me$$

    (C)$$\Rightarrow$$  $$(\pm)$$  $$ Ph-CH=CH-\underset{OH}{\underset {|}CH}-Me$$
    The products $$(B)$$ and $$(C)$$ are respectively
  • (B)$$\Rightarrow$$(-) $$Ph-\overset{OH}{\overset{|}CH}-CH=CH-Me$$

    (C)$$\Rightarrow$$ $$(\pm)$$ $$Ph-\underset{OH}{\underset{|}CH}-CH=CH-Me$$

    The products $$(B)$$ and $$(C)$$ are, respectively
Which of the following side chain reaction/s can be used to reduce the activity groups such as $$(OH)$$ or $$(-{NH}_{2})$$?
  • Benzoylation
  • Acetylation
  • Tosylation
  • Sulphonation
Consider the following reactions:
$$I. {Me}_{3}C-Br \xrightarrow [ { SN }^{ 1 } ]{ { H }_{ 2 }O+NaBr }  Products$$

$$II. {Ph}_{3}C-Br \xrightarrow [ { SN }^{ 1 } ]{ { H }_{ 2 }O+NaBr }  Products$$
Which of the following statements are correct about the above reactions?
  • The products in reactions $$(I)$$ and $$(II)$$ are mixture of $$({Me}_{3}-OH+{Me}_{3}Br)$$ and $$({Ph}_{3}C-OH+{Ph}_{3}C-Br)$$, respectively
  • The product in $$(I)$$ is $$({Me}_{3}C-OH)$$ and in $$(II)$$ is $$({Ph}_{3}C-OH+{Ph}_{3}C-Br)$$
  • The product in $$(I)$$ is $$({Me}_{3}C-OH)$$ and in $$(II)$$ is $$({Ph}_{3}C-OH)$$
  • $${Ph}_{3}{ C }^{ \oplus }$$ is more stable than $${Me}_{3}{ C }^{ \oplus }$$
Compounds $$(B)$$ and $$(C)$$ respectively are :
253027_7513d9fad8914e50b8f86852bbfab9f2.png
Which of the following synthesis could not be done without involving blocking position on the ring?
In which of the following reactions, the correct major product formed?
Consider the given reactions:
Which statement(s) is/are wrong?
251993.PNG
  • The product by path $$(I)$$ is $$Me-CH={CH}_{2}(I)$$
  • The product by path $$(II)$$ is $$Me-CH(OEt)Me(II)$$
  • The products are mixture of $$(I)$$ and $$(II)$$ by both paths
  • Path $$(I)$$ proceeds via E2 mechanism, while path $$II$$ proceeds via $${S_N}{1}$$ mechanism
Product $$(C)$$ is:
253038_ed57a9492dd34adea0e62dfae9ff795f.png
  • None of the above
I. $$CH_3CH_2I\xrightarrow[E2]{EtO^-} CH_2=CH_2+EtOH+I$$
II. $$D_3C-CH_2I\xrightarrow[E2]{EtO^-}D_2C=CH_2+EtOD+I$$

III. $$Me_3C-I\xrightarrow[SN^1 \ and\ E1]{EtO^-} Me_3C-OEt+(Me)_2C=CH_2$$

IV. $$(CD_3)_3C-I\xrightarrow[SN^1 and\ E1]{EtO^-}(CD_3)_3C-OEt+(CD_3)_2C=CD_2$$
Consider the given reactions.
Which of the following statement(s) is/are correct?
  • Reactions $$(I)$$ and $$(II)$$ show primary kinetic isotope effect, whereas reactions $$(III)$$ and $$(IV)$$ show $${2}^{o}$$ kinetic isotope effect
  • Reactions $$(I)$$ and $$(II)$$ show $${2}^{o}$$ kinetic isotope effect, whereas reactions $$(III)$$ and $$(IV)$$ show $${1}^{o}$$ kinetic isotope effect
  • All reactions show $${1}^{o}$$ kinetic isotope effect
  • All reactions show $${2}^{o}$$ kinetic isotope effect
Choose the incorrect reaction.
  • $$2{C}_{2}{H}_{5}I+2Na\xrightarrow [ ]{ { \left( { C }_{ 2 }{ H }_{ 5 } \right) }_{ 2 }O } {C}_{4}{H}_{10}+2NaI$$
  • $$2{C}_{2}{H}_{5}Br+Zn \xrightarrow [ ]{ EtOH } { \left( { C }_{ 2 }{ H }_{ 5 } \right) }_{ 2 }Zn+{Br}_{2}$$
  • $$2{C}_{2}{H}_{5}I+{Na}_{2}S \longrightarrow { \left( { C }_{ 2 }{ H }_{ 5 } \right) }_{ 2 }S+2NaI$$
  • $$2{C}_{2}{H}_{5}Br+NaI \xrightarrow [ ]{ { \left( { CH }_{ 3 } \right) }_{ 2 }C=O } {C}_{2}{H}_{5}I+NaBr$$
  • All are correct reations
Which of the given mentioned positions in the given compound is more reactive towards electrophilic substitutions?
253118_c7167dba8fa440de88616b1a12dadf6e.png
  • $$3$$
  • $$2$$
  • $$5$$
  • $$6$$
In the reaction $${CH}_{3}C\equiv  \overset { \oplus  }{ CNa } +{ \left( { CH }_{ 3 } \right)  }_{ 2 }CHCl\longrightarrow  $$ the product formed is:
  • $$4$$-Methyl-$$2$$-pentyne only
  • Propyne
  • Propyne and propylene
  • Mixture of propene, propyne, and $$4$$-methyl-$$2$$-pentyne
The yield of chlorobenzene obtained by reaction of phenols with $$P{Cl}_{5}$$ is less, due to the formation of :
  • o-chlorophenol
  • p-chlorophenol
  • phosphorus oxychloride
  • triphenyl phosphate
Which of the following sequence of reactions (reagents) can be used for the conversion of $$Ph{CH}_{2}{CH}_{3}$$ into $$PhCH={CH}_{2}$$?
  • $$SO{Cl}_{2};\ {H}_{2}O$$
  • $${SO}_{2}{Cl}_{2};\ alc. KOH$$
  • $${Cl}_{2}/hv;\ {H}_{2}O$$
  • $$SO{Cl}_{2}; \ alc. KOH$$
In the given reactions, the rate of reaction of $$(I)$$ is faster than that of $$(II)$$. By which mechanism do both reactions proceed?
253042_925c1fbfdc1f4a349648770e66788d48.png
  • E1
  • E2
  • E1cB
  • $$\alpha$$-Elimination
Bottles containing $$PhI$$ and $$Ph{CH}_{2}I$$ lost their original labels. They were labelled as $$(A)$$ and $$(B)$$ for testing. $$(A)$$ and $$(B)$$ were separately taken in test tubes and boiled with $$NaOH$$ solutions. The end solution in each tube was made acidic with dilutie $$H{NO}_{3}$$ and some $$Ag{NO}_{3}$$ solution was added. Substance $$(B)$$ gave a yellow precipitate. Which of the following statements is true for this experiment?
  • Addition of $$H{NO}_{3}$$ was unnecessary
  • $$(A)$$ was $$PhI$$
  • $$(A)$$ was $$Ph{CH}_{2}I$$
  • $$(B)$$ was $$PhI$$
The product on monobromination of this compound is :
254290_f740a83c956a4179a0481c88b3972d55.png
Which one of the following compound will give $$S_{N}1$$ reaction predominantly?
  • None of these
$$Cl^-\;\;\;\;\;\;\;\;\;\;\;\;CH_3O^-\;\;\;\;\;\;\;\;\;\;\;\;CH_3S^-\;\;\;\;\;\;\;\;\;\;\;\;I^-$$
$$(I)\;\;\;\;\;\;\;\;\;\;\;\;(II)\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;\;(III)\;\;\;\;\;\;\;\;\;\;\;\;(IV)$$
The correct order of increasing leaving group capability of above anions:
  • $$III < IV < II < I$$
  • $$II < III < I < IV$$
  • $$II < IV < III < I$$
  • $$I < III < II < IV$$
Among the following which is feasible?
  • $$\;X^-+CH_3-CH_2-H\longrightarrow CH_3-CH_2-X+H^-$$
  • $$\;X^-+CH_3-OH\longrightarrow CH_3-X+\bar{O}H$$
  • $$\;{X}\bar+H_3C-\overset { \oplus }{ \underset { \underset { H }{ \mid } }{ O } } H\longrightarrow CH_{ 3 }-X+ H_{ 2 }O$$
  • $$\;X^-+CH_3-CH_3\longrightarrow CH_3-X+\bar{C}H_3$$
Vinyl chloride does not give $$S_N$$ reaction but allyl chloride does. because ______________.
  • in vinyl chloride, $$C\,-\,Cl$$ bond is stable due to resonance.
  • in allyl chloride, $$C\,-\,Cl$$ bond is stable due to resonance.
  • vinyl carbocation formed by removal of $$Cl^\ominus$$ is stable due to resonance.
  • allyl carbocation formed by removal of $$Cl^\ominus$$ is stable due to resonance.
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