CBSE Class 12 Chemistry Haloalkanes and Haloarenes MCQs Set B

Question. The reaction of C₆H₅CH CHCH₃ with HBr produces
(a) C₆H₅CH₂CH₂CH₂Br
The reaction will be most favourable if M happens to be
(a) Na
(b) K
(c) Rb
(d) Li

Answer : C

Question. When chlorine is passed through propene at 400°C,which of the following is formed?
(a) PVC
(b) Allyl chloride
(c) Propyl chloride
(d) 1, 2-Dichloroethane

Answer : B

Question. Elimination reaction of 2-bromopentane to form pent-2-ene is
(A) b-Elimination reaction
(B) Follows Zaitsev rule
(C) Dehydrohalogenation reaction
(D) Dehydration reaction
(a) (A), (B), (C)
(b) (A), (C), (D)
(c) (B), (C), (D)
(d) (A), (B), (D)

Answer : A

Question. The compound A on treatment with Na gives B, and with PCl₅ gives C. B and C react together to give diethyl ether. A, B and C are in the order
(a) C₂H₅OH, C₂H₆, C₂H₅Cl
(b) C₂H₅OH, C₂H₅Cl, C₂H₅ ONa
(c) C₂H₅Cl, C₂H₆, C₂H₅ OH
(d) C₂H₅OH, C₂H₅ONa, C₂H₅ Cl

Answer : D

Question. The compound C7H8 undergoes the following reactions :
The product C is
(a) m-bromotoluene
(b) o-bromotoluene
(c) 3-bromo-2,4,6-trichlorotoluene
(d) p-bromotoluene.

Answer : A

Question. Chlorination of toluene in the presence of light and heat followed by treatment with aqueous NaOH gives
(a) o-cresol
(b) p-cresol
(c) mixture of o-cresol and p-Cresol
(d) benzoic acid
(e) 1, 3, 5-trihydroxy toluene

Answer : C

Question. How many stereoisomers does this molecule have? CH₃CH CHCH₂CHBrCH₃
(a) 8
(b) 2
(c) 4
(d) 6

Answer : C

Question. If there is no rotation of plane polarised light by a compound in a specific solvent, though to be chiral, it may mean that
(a) the compound is certainly meso
(b) there is no compound in the solvent
(c) the compound may be a racemic mixture
(d) the compound is certainly a chiral.

Answer : A

Question. Which of the following is not chiral?
(a) 2-Hydroxypropanoic acid
(b) 2-Butanol
(c) 2,3-Dibromopentane
(d) 3-Bromopentane

Answer : D

Question. Which of the following undergoes nucleophilic substitution exclusively by SN₁ mechanism?
(a) Ethyl chloride
(b) Isopropyl chloride
(c) Chlorobenzene
(d) Benzyl chloride

Answer : D

Question. Chlorobenzene reacts with Mg in dry ether to give a compound (A) which further reacts with ethanol to yield
(a) phenol
(b) benzene
(c) ethyl benzene
(d) phenyl ether.

Answer : B

Question. Benzene reacts with n-propyl chloride in the presence of anhydrous AlCl₃ to give
(a) 3-propyl-1-chlorobenzene
(b) n-propylbenzene
(c) no reaction
(d) isopropylbenzene.

Answer : D

Question. Which of the following is an optically active compound?
(a) 1-Butanol
(b) 1-Propanol
(c) 2-Chlorobutane
(d) 4-Hydroxyheptane

Answer : C

Question. Industrial preparation of chloroform employs acetone and
(a) phosgene
(b) calcium hypochlorite
(c) chlorine gas
(d) sodium chloride.

Answer : B

Question. Phosgene is a common name for
(a) phosphoryl chloride
(b) thionyl chloride
(c) carbon dioxide and phosphine
(d) carbonyl chloride.

Answer : D

Question. Which of the following reactions is an example of nucleophilic substitution reaction?
(a) 2RX + 2Na R – R + 2NaX
(b) RX + H2 RH + HX
(c) RX + Mg RMgX
(d) RX + KOH ROH + KX

Answer : D

Question. Which of the following statements about benzyl chloride is incorrect?
(a) It is less reactive than alkyl halides
(b) It can be oxidised to benzaldehyde by boiling with copper nitrate solution
(c) It is a lachrymatory liquid and answers Beilstein’s test
(d) It gives a white precipitate with alcoholic silver nitrate

Answer : A

Question. The reaction of toluene with Cl₂ in presence of FeCl₃ gives predominantly
(a) benzoyl chloride
(b) benzyl chloride
(c) o and p-chlorotoluene
(d) m-chlorotoluene

Answer : C

Question. Decomposition of benzene diazonium chloride by using Cu₂Cl₂ / HCI to form chlorobenzene is 
(a) Raschig reaction
(b) Sandmeyer’s reaction
(c) Kolbe’s reaction
(d) Cannizzaro’s reaction

Answer : B

Question. Grignard reagent is prepared by the reaction between
(a) magnesium and alkane
(b) magnesium and aromatic hydrocarbon
(c) zinc and alkyl halide
(d) magnesium and alkyl halide.

Answer : D