Haloalkanes & Haloarenes MCQ Class 12: Haloalkanes और Haloarenes कक्षा 12 की ऑर्गेनिक केमिस्ट्री का एक महत्वपूर्ण अध्याय है। इस अध्याय में उन कार्बनिक यौगिकों का अध्ययन किया जाता है जिनमें कार्बन परमाणु के साथ हैलोजन तत्व (F, Cl, Br, I) जुड़े होते हैं। Haloalkanes में हैलोजन परमाणु sp³ hybridized carbon से जुड़े होते हैं, जबकि Haloarenes में हैलोजन aromatic ring से जुड़े होते हैं।
इस अध्याय में मुख्य रूप से न्यूक्लियोफिलिक सब्स्टीट्यूशन रिएक्शन (SN1 और SN2), एलिमिनेशन रिएक्शन, Grignard reagent, तथा Haloalkanes और Haloarenes की रासायनिक अभिक्रियाओं का अध्ययन किया जाता है। यह टॉपिक CBSE Board Exam, NEET और JEE जैसी परीक्षाओं के लिए बहुत महत्वपूर्ण है, क्योंकि यहाँ से हर साल कई MCQ और Assertion–Reason प्रश्न पूछे जाते हैं।
इस पोस्ट में Haloalkanes और Haloarenes से जुड़े 50 महत्वपूर्ण MCQ प्रश्न उत्तर सहित दिए गए हैं, जो आपकी कक्षा 12 बोर्ड परीक्षा 2026 की तैयारी को मजबूत करने में मदद करेंगे। इन प्रश्नों को हल करके आप इस अध्याय के महत्वपूर्ण कॉन्सेप्ट को जल्दी और आसानी से दोहरा सकते हैं।
Haloalkanes & Haloarenes MCQ Class 12: 50 महत्वपूर्ण MCQ प्रश्न उत्तर सहित
1. Haloalkanes are derivatives of alkanes in which hydrogen atom is replaced by:
(a) Oxygen
(b) Nitrogen
(c) Halogen
(d) Sulphur
Answer: (c) Halogen
2. Which of the following is an example of haloalkane?
(a) CH₃OH
(b) CH₃Cl
(c) CH₃NH₂
(d) CH₃CHO
Answer: (b) CH₃Cl
3. Which halogen has the highest electronegativity?
(a) Chlorine
(b) Bromine
(c) Iodine
(d) Fluorine
Answer: (d) Fluorine
4. The general formula of haloalkanes is:
(a) R–OH
(b) R–X
(c) R–NH₂
(d) R–COOH
Answer: (b) R–X
5. In nucleophilic substitution reactions the attacking species is:
(a) Electrophile
(b) Radical
(c) Nucleophile
(d) Catalyst
Answer: (c) Nucleophile
6. Which solvent favors SN1 reaction?
(a) Non-polar solvent
(b) Polar protic solvent
(c) Inert solvent
(d) Hydrocarbon solvent
Answer: (b) Polar protic solvent
7. Which compound will undergo SN1 reaction fastest?
(a) CH₃Cl
(b) CH₃CH₂Cl
(c) (CH₃)₃CCl
(d) CH₃CH₂CH₂Cl
Answer: (c) (CH₃)₃CCl
8. Which compound undergoes SN2 reaction fastest?
(a) CH₃Br
(b) (CH₃)₂CHBr
(c) (CH₃)₃CBr
(d) CH₃CH₂CH₂Br
Answer: (a) CH₃Br
9. Which reagent is used to convert alcohol to haloalkane?
(a) KMnO₄
(b) NaOH
(c) PCl₅
(d) H₂SO₄
Answer: (c) PCl₅
10. Which test is used to detect halogens in organic compounds?
(a) Molisch test
(b) Beilstein test
(c) Fehling test
(d) Tollen test
Answer: (b) Beilstein test
11. Ethyl chloride on hydrolysis forms:
(a) Ethane
(b) Ethanol
(c) Ethene
(d) Ethanoic acid
Answer: (b) Ethanol
12. Which reagent converts haloalkane to alcohol?
(a) HCl
(b) Aqueous KOH
(c) NaCl
(d) H₂SO₄
Answer: (b) Aqueous KOH
13. Haloalkanes react with KCN to form:
(a) Alcohol
(b) Amine
(c) Alkyl cyanide
(d) Ketone
Answer: (c) Alkyl cyanide
14. Which of the following is most reactive towards nucleophilic substitution?
(a) R–F
(b) R–Cl
(c) R–Br
(d) R–I
Answer: (d) R–I
15. Wurtz reaction involves:
(a) Formation of alcohol
(b) Formation of aldehyde
(c) Coupling of haloalkanes
(d) Oxidation of alcohol
Answer: (c) Coupling of haloalkanes
16. In Wurtz reaction the reagent used is:
(a) KOH
(b) Sodium metal
(c) HCl
(d) NH₃
Answer: (b) Sodium metal
17. Which of the following is an example of haloarene?
(a) CH₃Cl
(b) C₆H₅Cl
(c) CH₃Br
(d) CH₃I
Answer: (b) C₆H₅Cl
18. Chlorobenzene reacts with NaOH at high temperature to form:
(a) Benzene
(b) Phenol
(c) Benzoic acid
(d) Benzaldehyde
Answer: (b) Phenol
19. Which of the following is a primary haloalkane?
(a) (CH₃)₃CCl
(b) (CH₃)₂CHCl
(c) CH₃CH₂Cl
(d) None
Answer: (c) CH₃CH₂Cl
20. Secondary haloalkane example is:
(a) CH₃Cl
(b) CH₃CHClCH₃
(c) (CH₃)₃CCl
(d) CH₃CH₂CH₂Cl
Answer: (b) CH₃CHClCH₃
21. Tertiary haloalkane example is:
(a) CH₃Cl
(b) CH₃CH₂Cl
(c) (CH₃)₃CCl
(d) CH₃CH₂CH₂Cl
Answer: (c) (CH₃)₃CCl
22. Which reaction mechanism forms carbocation intermediate?
(a) SN2
(b) SN1
(c) E2
(d) Free radical
Answer: (b) SN1
23. Which mechanism is bimolecular?
(a) SN1
(b) SN2
(c) E1
(d) Radical
Answer: (b) SN2
24. SN2 reaction proceeds with:
(a) Racemization
(b) Inversion of configuration
(c) Retention
(d) Polymerization
Answer: (b) Inversion of configuration
25. Elimination reaction of haloalkane forms:
(a) Alcohol
(b) Alkane
(c) Alkene
(d) Ketone
Answer: (c) Alkene
26. Which base is used in elimination reaction?
(a) Dilute HCl
(b) Alcoholic KOH
(c) NaCl
(d) NH₄Cl
Answer: (b) Alcoholic KOH
27. Grignard reagent is prepared from:
(a) Alcohol
(b) Haloalkane
(c) Aldehyde
(d) Alkene
Answer: (b) Haloalkane
28. Grignard reagent contains metal:
(a) Sodium
(b) Potassium
(c) Magnesium
(d) Lithium
Answer: (c) Magnesium
29. Formula of Grignard reagent is:
(a) R–Cl
(b) RMgX
(c) R–OH
(d) R–NH₂
Answer: (b) RMgX
30. Which haloalkane gives alcohol with moist silver oxide?
(a) R–X
(b) R–OH
(c) R–NH₂
(d) R–CHO
Answer: (a) R–X
31. Haloarenes are less reactive towards nucleophilic substitution because of:
(a) Weak bond
(b) Resonance stabilization
(c) Low polarity
(d) High boiling point
Answer: (b) Resonance stabilization
32. Which reaction forms alkene from haloalkane?
(a) Substitution
(b) Elimination
(c) Addition
(d) Oxidation
Answer: (b) Elimination
33. Vinyl chloride belongs to:
(a) Haloalkane
(b) Haloalkene
(c) Haloarene
(d) Alkane
Answer: (b) Haloalkene
34. Haloalkenes contain halogen attached to:
(a) sp³ carbon
(b) sp² carbon
(c) sp carbon
(d) Aromatic ring
Answer: (b) sp² carbon
35. Which compound is haloalkene?
(a) CH₃Cl
(b) CH₃CH₂Cl
(c) CH₂=CHCl
(d) CH₃Br
Answer: (c) CH₂=CHCl
36. Haloalkenes show:
(a) SN1 easily
(b) SN2 easily
(c) Low nucleophilic substitution
(d) High substitution
Answer: (c) Low nucleophilic substitution
37. PVC is obtained from polymerization of:
(a) Ethene
(b) Propene
(c) Vinyl chloride
(d) Ethyne
Answer: (c) Vinyl chloride
38. Vinyl chloride formula is:
(a) CH₃Cl
(b) CH₂=CHCl
(c) CH₃CH₂Cl
(d) CH₃Br
Answer: (b) CH₂=CHCl
39. Which reaction converts alkene to haloalkane?
(a) Addition of HX
(b) Hydrolysis
(c) Oxidation
(d) Reduction
Answer: (a) Addition of HX
40. Markovnikov rule applies to:
(a) Substitution
(b) Addition reactions
(c) Elimination
(d) Reduction
Answer: (b) Addition reactions
41. Anti-Markovnikov addition occurs in presence of:
(a) Acid
(b) Peroxide
(c) Base
(d) Catalyst
Answer: (b) Peroxide
42. Which haloalkane has highest boiling point?
(a) CH₃Cl
(b) CH₃Br
(c) CH₃I
(d) CH₃F
Answer: (c) CH₃I
43. Which factor affects reactivity of haloalkanes?
(a) Bond strength
(b) Polarity
(c) Structure
(d) All of these
Answer: (d) All of these
44. Which compound forms AgCl precipitate with AgNO₃?
(a) CH₃Cl
(b) CH₄
(c) CH₃OH
(d) CH₃CHO
Answer: (a) CH₃Cl
45. Haloalkanes are generally:
(a) Highly soluble in water
(b) Insoluble in water
(c) Strong acids
(d) Strong bases
Answer: (b) Insoluble in water
46. Which compound reacts fastest with NaOH?
(a) CH₃Cl
(b) CH₃Br
(c) CH₃I
(d) CH₃F
Answer: (c) CH₃I
47. Haloalkanes react with ammonia to form:
(a) Alcohol
(b) Amine
(c) Ketone
(d) Ester
Answer: (b) Amine
48. Reaction of haloalkane with AgNO₂ gives:
(a) Alcohol
(b) Nitroalkane
(c) Amine
(d) Alkene
Answer: (b) Nitroalkane
49. Haloalkanes react with sodium metal in dry ether to form:
(a) Alcohol
(b) Higher alkane
(c) Alkene
(d) Ester
Answer: (b) Higher alkane
50. Haloalkanes are also called:
(a) Alkyl halides
(b) Alcohols
(c) Ketones
(d) Ethers
Answer: (a) Alkyl halides