MCQ Chapter 10 Haloalkanes and Haloarenes Class 12 Chemistry

Please refer to Haloalkanes And Haloarenes MCQ Questions Class 12 Chemistry below. These MCQ questions for Class 12 Chemistry with answers have been designed as per the latest NCERT, CBSE books and syllabus issued for the current academic year. These objective questions for Haloalkanes And Haloarenes will help you to prepare for the exams and get more marks.

Haloalkanes And Haloarenes MCQ Questions Class 12 Chemistry

Please see solved MCQ Questions for Haloalkanes And Haloarenes in Class 12 Chemistry. All questions and answers have been prepared by expert faculty of standard 12 based on latest examination guidelines.

Question. CH₃Br + Nu^– → CH₃ —Nu + Br^– . The decreasing order of the rate of the above reaction with nucleophiles (Nu^–) A to D is
 [Nu^– = (A) PhO^–, (B) AcO^– , ( C) HO^– ],(D) CH₃O^– )      
(a) D > C > A > B
(b) D > C > B > A 
(c) A > B > C > D
(d) B > D > C > A   

Question. An incorrect statement with respect to S_N1 and S_N2 mechanisms of alkyl halide is 
(a) a strong nucleophile in an aprotic solvent increases the rate or favours S_N2 reaction
(b) competing reaction for a S_N2 reaction is rearrangement
(c) S_N1 reactions can be catalysed by some Lewis acids
(d) a weak nucleophile and aprotic solvent increases the rate or favours S_N1 reaction   

Question. Reaction of trans-2-phenyl-l-bromo reaction with alcoholic KOH produces cyclopentane on
(a) 4-phenyl cyclopentene
(b) 2-phenyl cyclopentene
(c) 1-phenyl cyclopentene
(d) 3-phenyl cyclopentene     

Question. Which of the following haloalkanes would undergo reaction faster? 

(a) Only I
(b) Only II
(c) Only III
(d) Only IV       

Question. The molecular formula of diphenyl methane

 How many structural isomers are possible when one of the hydrogen is replaced by a chlorine atom? 
(a) 6
(b) 4
(c) 8
(d) 7     

Question. Of the five isomeric hexanes, the isomer which can give two monochlorinated compounds is 
(a) 2-methy 1 pentane
(b) 2, 2-dimethy 1 butane
(c) 2, 3-dimethyl butane
(d) n-hexane     

Question. In S_N 2 reactions, the correct order of reactivity for the following compounds CH₃ Cl, CH₃CH₂ Cl, (CH₃)₂ CHCI and (CH₃)₃ CCI is
(a) CH₃CI > (CHH₃)₂ CHCI > CH₂CH₂CI > (CH₃)₃ CCI
(b) CH₃Cl > CH₃CH₂Cl > (CH₃)₃ CHCI > (CH₃)₃CCI
(c) CH₃CH₂Cl > CH₃Cl > (CH₃ )₂ CHCI >(CH₃)₃ CCI
(d) (CH₃)₂ CHCI > CH₃CH₂Cl > CH₃Cl > (CH₃)₃ CCI     

Question. What will be the product of the reaction,

Question. Arrange the following compounds in the increasing order of their boiling points. 

(a) II < I < III
(b) I < II < III
(c) III < I < II
(d) III < II < I       

Question. Which reagents would you use to carry out the reaction Ethyl benzene → 2 and 4-chloro- 1 -ethyl benzene?
(a) Cl₂, light and heat 
(b) Cl₂, FeCl₃
(c) SOCl₂
(d) C₂H₅CI, AICl₃     

Question. 9.65 C of electric current is passed through fused anhydrous magnesium chloride. The magnesium metal thus, obtained is completely converted into a Grignard reagent. The number of moles of the Grignard reagent obtained is 
(a) 5 x 10^-4
(b) 1 x 10^-4
(c) 5 x 10^-5
(d) 1 x 10^-5     

Question. Which one of the following forms propane nitrile as the major product? 
(a) Ethyl bromide + alcoholic KCN
(b) Propyl bromide + alcoholic KCN
(c) Propyl bromide + alcoholic AgCN
(d) Ethyl bromide + alcoholic AgCN     

Question. Tertiary butyl alcohol gives tertiary butyl chloride on treatment with 
(a) cone. HCl/anhy. ZnCl₂
(b) KCN
(c) NaOCI
(d) Cl₂     

Question. The product of reaction between alcoholic silver nitrite with ethyl bromide is 
(a) ethene
(b) ethane
(c) ethyl nitrile
(d) nitro ethane   

Question. Which of the following is not true for the hydrolysis of t-butyl bromide with aqueous NaOH? 
(a) Reaction occurs through the S_N1 mechanism
(b) The intermediate formed is a carbocation
(c) Rate of the reaction doubles when the concentration of alkali is doubled
(d) Rate of the reaction doubles when the concentration of t-butyl bromide is doubled   

Question. Grignard reagent is not prepared in aqueous medium but prepared in either medium, because 
(a) the reagent is highly reactive in ether
(b) the reagent does not react with water
(c) the reagent becomes inactive in water
(d) the reagent reacts with water       

Question. Ethyl iodide when heated with sodium in dry ether gives pure 
(a) C₄H₁₀
(b) C₂H₆
(c) C₃H₈
(d) C₂H₅OH   

Question. 2-bromopentane with ale. KOH yields a mixture of three alkenes. Which of the following alkene is predominant?
(a) 1-pentene
(b) Cis-2-pentene 
(c) Trans-2-pentene
(d) Cis-1-pentene       

Question. Number of monochloro derivatives obtained when neo-pentane is chlorinated, is
(a) one
(b) two
(c) three
(d) four     

Question. The catalyst used in the preparation of an alkyl chloride by the action of dry HCI on an alcohol is
(a) anhy. AlCl₃ 
(b) FeCl₃
(c) anhy. ZnCl₂
(d) Cu     

Question. t-butyl chloride preferably undergo hydrolysis by 
(a) S_N1 mechanism
(b) S_N2 mechanism
(c) Any of(a) and (b)
(d) None of the above         

Question. In the following sequence of reactions, 
C₂H₅Br →^AgCN X →^Reduction Y , Y IS
(a) n-propylamine
(b) iso-propylamine
(c) ethylamine Reduction 
(d) ethyl methyl amine   

Question. Alkyl halides are less soluble in water because
(a) they ionise in water
(b) they do not form H-bonds with water
(c) they are highly viscous
(d) they have very strong C—X bond       

Question. Predict the product, 

Question. X + KCN → CH₃CN →^2H₂/Ni CH₃CH₂NH₂ What is X ? 
(a) CH₃CH₂Cl
(b) CH₃CI
(c) CH₃CH₂CH₂Cl
(d) (CH₃)₂CHCl     

Question. 1-chlorobutane on reaction with alcoholic potash gives
(a) 1-butene
(b) 1-butanol 
(c) 2-butene
(d) 2-butanol     

Question. The organic chloro compound, which shows complete stereochemical inversion during an S_N2 reaction is
(a) (C₂H₅)₂CHCl
(b) (CH₃)₃CCl
(c) (CH₃)₂CHCl
(d) CH₃Cl       

Question. On treating a mixture of two alkyl halides with sodium metal in dry ether, 2-methyl propane was obtained. The alkyl halides are 
(a) 2-chloropropane and chloromethane
(b) 2-chloropropane and chloroethane
(c) chloromethane and chloroethane
(d) chloromethane and 1-chloropropane     

Question. Which of the following compounds has the highest boiling point? 
(a) CH₃CH₂CH₂Cl
(b) CH₃CH₂CH2CH₂Cl
(c) CH₃CH(CH₃)CH₂Cl
(d) (CH₃)₃ CCI     

Question. 1 , 2-dibromoethane reacts with alcoholic KOH to yield a productX. The hybridisation state of the carbons present in X respectively, are 
(a) sp ,sp
(b) sp³ , sp³
(c) sp³ , sp²
(d) sp³ , sp²   

Question. In the reaction, 2A + dry silver oxide →^Δ ether+ 2Ag X A is a /an 
(a) primary alcohol
(b) acid
(c) alkyl halide
(d) alcohol       

Question. Which of the following haloalkanes is most reactive?
(a) 1-chloropropane
(b) 1-bromopropane 
(c) 2-chloropropane
(d) 2-bromopropane     

Question. 1-chlorobutane on reaction with alcoholic potash gives
(a) but-1-ene
(b) butane-1-ol 
(c) but-2-ene
(d) butane-2-ol       

Question. An alkyl halide reacts with alcoholic ammonia in a sealed tube, the product formed will be
(a) a primary amine
(b) a secondary amine
(c) a tertiary amine
(d) All of the above       

Question. Anti-Markownikoff’s addition of HBr is observed in
(a) propane
(b) but-2-ene
(c) pent-2-ene
(d) All of the above     

Question. Which of the following alkyl halides is used as a methylating agent?
(a) C₂H₅Br
(b) C₆H₅Cl
(c) CH₃CI
(d) C₂H₅Cl       

Question. CH₃Br + KCN (ale. ) → X Reduction→_{Na +C2H5 OH} Y. What is Y in the series ? 
(a) CH₃CN
(b) C₂H₅CN
(c) C₂H₅NH₂
(d) CH₃NH₂       

Question. In a group of isomeric alkyl halides, the order of boiling points is 
(a) primary < secondary < tertiary
(b) primary > secondary < tertiary
(c) primary < secondary > tertiary
(d) primary > secondary > tertiary     

Question. The order ofreactivities of methyl halides in the formation of Grignard reagent is 
(a) CH₃l > CH₃Br > CH₃CI
(b) CH₃Cl > CH₃Br > CH₃I
(c) CH₃Br > CH₃CI > CH₃I
(d) CH₃Br > CH₃l > CH₃Cl     

Question. Alkyl halide is converted into alcohol. This is an example of …… reaction. 
(a) addition
(b) displacement
(c) substitution
(d) complex     

Question. Maximum number of molecules of CH₃l that can react with a molecule of CH₃NH₂ are 
(a) 3
(b) 4
(c) 2
(d) 1       

Question. Match the following columns.

Codes
     A B C D
(a) 5 3 4 1
(b) 1 2 3 4
(c) 3 4 1 2
(d) 4 1 4 2         

Question. The conversion of ethyl chloride into diethyl ether takes place by 
(a) Williamson’s synthesis
(b) Perkin’s reaction
(c) Wurtz reaction
(d) Grignard reaction     

Question. The structure of the major product formed in the following reaction is 

Question. CH₃Br + OH → CH₃OH + Br^– reaction proceeds by S_N2 mechanism. Its rate is dependent on the concentration of 
(a) CH₃Br, OH
(b) Only CH₃Br
(c) Only OH
(d) CH₃Br, CH₃OH     

Question. Which one of the following is not fom1ed when a mixture of methyl bromide and bromobenzene is heated with sodium metal in the presence of dry ether? 
(a) Diphenyl
(b) Propane
(c) Toluene
(d) Ethane     

Question. RX+ A → RNC,A is
(a) AgCN
(b) KCN
(c) NaCN
(d) HCN     

Question. Ethyl chloride on heating with AgCN forms a compound X. The functional isomer of X is 
(a) C₂H₅NC
(b) C₂H₅NH₂
(c) C₂H₅CN
(d) None of these       

Question. Which of the following statements regarding the S_N1 reaction shown by alkyl halide is not correct?
(a) The added nucleophile plays no kinetic role in S_N1 reaction
(b) The S_N1 reaction involves the inversion of configuration of the optically active substrate
(c) The S_N1 reaction on the chiral starting material ends up with racemisation of the product
(d) The more stable the carbocation intermediate the faster the S_N1 reaction
(e) Polar pro tic solvent increases the rate of S_N1 reaction.     

Question. The best method for the conversion of an alcohol into an alkyl chloride is by treating the alcohol with
(a) PCl₃
(b) PCl₅
(c) SOCl₂ in the presence of pyridine
(d) dry HCl in the presence of anhydrous ZnCI₂   

Question. The final product, in the below reaction, is 

Question. Compound ‘A’ reacts with alcoholic KOH to yield compound ‘B ‘, which on ozonolysis followed by reaction with Zn /H₂O gives methanal and propanal. Compound ‘A’ is 
(a) 1-propanol
(b) 1-butanol
(c) 1-chlorobutane
(d) 1-chloropentane   

Question. Identify A and B in the following reactions
A →^{Aq. NaOH} C₂H₅ OH ^AgOH_← B
(a) A = C₂H₂, B = C₂H₆
(b) A = C₂H₅ Cl,B = C₂H₄
(c) A = C₂H₄ , B = C₂H₅ Cl
(d) A = C₂H₅ Cl,B = C₂H₅ Cl       

Question. The order of reactivities of methyl halides in the formation of Grignard reagent is 
(a) CH₃I > CH₃Br > CH₃CI
(b) CH₃CI > CH₃Br > CH₃I
(c) CH₃Br > CH₃CI > CH₃I
(d) CH₃Br > CH₃I > CH₃CI     

Question. Tertiary alkyl halides are practically inert to substitution by S_N2 mechanism because of
(a) steric hindrance
(b) inductive effect
(c) instability
(d) insolubility       

Question. Which of the following applies in the reaction,
CH₃CHBrCH₂CH₃ →^{Ale. KOH}
I. CH₃CH = CHCH₃ (major product)
II. CH₂ = CHCH₂CH₃ (minor product)
(a) Markownikoff’s rule
(b) Saytzeff’s rule
(c) Kharasch effect
(d) Hofrnann’s rule     

Question. Identify X and Y in the following sequence :
C₂H₅ Br → product → C₃H₇NH₂
(a) X = KCN,Y = LiAIH₄
(b) X = KCN,Y = H₃O₊
(c) X = CH₃Cl,Y = AlCl₃ / HCI
(d) X = CH₃NH₂ ,Y = HNO₂       

Question. Elimination of bromine from 2-bromobutane results in the formation of
(a) predominantly 2-butyne
(b) predominantly 1-butene
(c) predominantly 2-butene
(d) equimolar mixture of 1 and 2-butene     

Question. When 32.25 g of ethyl chloride is subjected to dehydrohalogenation reaction the yield of the alkene formed is 50%. The mass of the product formed is (atomic mass of chlorine is 35.5)
(a) 14 g
(b) 28 g
(c) 64.5 g
(d) 56 g
(e) 7 g     

Question. Which halide does not get hydrolysed by sodium hydroxide? 
(a) Vinyl chloride
(b) Methyl chloride
(c) Ethyl chloride
(d) Iso-propyl chloride   

Question. An alkyl halide (RX) reacts with Na to form 4, 5-diethyloctane. Compound RX is
(a) CH₃ (CH₂)₃ Br
(b) CH₃ (CH₂)₂CH(Br)CH₂CH₃
(c) CH₃ (CH₂)₃CH(Br)CH₃
(d) CH₃ (CH₂)₅ Br
(e) CH₃Br     

Question. Which one of the following is more readily hydrolysed by S_N1 mechanism? 
(a) (C₆H₅)₂ C(CH₃)₂
(b) C₆H₅CH₂Br
(c) C₆H₅CH(CH₃) Br
(d) (C₆H₅)₂ CHBr   

Question. Alkyl iodide reacts with NaCN to give alkyl cyanide and small amount of alkyl isocyanide. Fom1ation of these two products is due to the 
(a) ionic character of NaCN
(b) nucleophilic character of CN^–
(c) ambidentate character of CN^–
(d) electrophilic character of CN^–     

Question. The following compound on hydrolysis in aqueous acetone will give 

(a) mixture of(K) and (L)
(b) mixture of(K) and (M)
(c) Only (M)
(d) Only (K)     

Question. Of the isomeric hexanes, the isomers that give the minimum and maximun number of monochloro derivatives are respectively 
(a) 3-methyl pentane and 2, 3-dimethyl butane
(b) 2, 3-dimethy 1 butane and n-hexane
(c) 2, 2-dimethye 1 butane and 2-methy 1 pentane
(d) 2, 3-dimethy 1 butane and 2-methy 1 pentane
(e) 2-methyl pentane and 2, 2-dimethylbutane   

Question. Following is the substitution reaction in which —CN replaces —CL
R—Cl + KCN_Alcoholic →^Δ R—CN + KCl
To obtain propane nitrile, R—Cl should be 
(a) chloroethane
(b) 1-chloropropane
(c) chloromethane
(d) 2-chloropropane