This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Chemistry Part Ii > Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes – Quiz 2 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 2 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Which of the following is not the method of preparation of alkyl halide? A) Addition of HX on alkenes. B) Darzen's method. C) Hydration of alkene. D) Halogenation of alkene. Show Answer Correct Answer: C) Hydration of alkene. 2. Assertion (A):Hydrolysis of (-)-2-bromooctane proceeds with inversion of configuration.Reason (R):This reaction proceeds through the formation of a carbocation. A) Assertion and Reason both are correct and Reason is the correct explanation of Assertion. B) Assertion and Reason both are correct statements but Reason is not the correct explanation of Assertion. C) Assertion is correct but Reason is wrong. D) Assertion is wrong but Reason is correct. Show Answer Correct Answer: C) Assertion is correct but Reason is wrong. 3. What type of halides are formed when halogen atoms are bonded to sp2 hybridized carbon atoms? A) Alkyl halides. B) Allylic halides. C) Vinylic halides. D) Aryl halides. Show Answer Correct Answer: D) Aryl halides. 4. What is the IUPAC name for CH3CH2CH2Br? A) 1-bromopropane. B) 3-bromopropane. C) 2-bromopropane. D) 1-chloropropane. Show Answer Correct Answer: A) 1-bromopropane. 5. Elimination R-X (eliminate H+, X-not combined). base (OH-) attacks H atom adjacent to X. no intermediate.follow Zaitsev rule.example:2-chlorobuthane $\rightarrow$ 2-butene (major) + 1-butene (minor). 2-chlorobutane (-HCl) $\rightarrow$ CH3-CH=CH-CH3 (major) + CH3CH2CH=CH2 (minor) A) R-X + KOH (ethanolic, heat) $\rightarrow$ C=C + KX + H2O. B) R-X + KOH (ethanolic, heat) $\rightarrow$ ROH + KX. C) All the above. D) None of the above. Show Answer Correct Answer: A) R-X + KOH (ethanolic, heat) $\rightarrow$ C=C + KX + H2O. 6. Among the choice alkyl bromide, the least reactive bromide in S$_{N}$2 reaction A) 2-bromo-2-methylbutane. B) 1-bromo-3-methylbutane. C) 1-bromo-2-methylbutane. D) 1-bromopentane. Show Answer Correct Answer: A) 2-bromo-2-methylbutane. 7. What is the expected product when chlorobenzene undergoes nitration? A) Nitrobenzene. B) Ortho-nitrochlorobenzene and para-nitrochlorobenzene. C) Chloronitrobenzene. D) Benzene. Show Answer Correct Answer: B) Ortho-nitrochlorobenzene and para-nitrochlorobenzene. 8. A dihalogen derivative 'X' of a hydrocarbon with three carbon atoms react with ale. KOH and produces hydrocarbon which forms red ppt. with ammonical Cu2Cl2. 'X' gives an aldehyde on reaction with aq. KOH. The compound 'X' is A) 2, 2-Dichloropropane. B) 1, 2-Dichloropropane. C) 1, 3-Dichloropropane. D) 1, 1-Dichloropropane. Show Answer Correct Answer: D) 1, 1-Dichloropropane. 9. Alkyl halides react with metallic sodium in dry ether producing A) Alkenes with same no. of carbon atoms. B) Alkanes with double the no. of carbon atoms. C) Alkenes with triple the no. of carbon atoms. D) Alkanes with same no. of carbon atoms. Show Answer Correct Answer: B) Alkanes with double the no. of carbon atoms. 10. Which haloalkane is most reactive in nucleophilic substitution reactions? A) Secondary haloalkanes. B) Tertiary haloalkanes. C) Primary haloalkanes. D) Alkyl halides. Show Answer Correct Answer: B) Tertiary haloalkanes. 11. How do you name a haloalkane with a branched chain? A) Ignore halo groups when naming. B) Count all carbon atoms in the molecule. C) Use only the longest branch for naming. D) Identify the longest chain, number it, name halo groups and branches, combine into a single name. Show Answer Correct Answer: D) Identify the longest chain, number it, name halo groups and branches, combine into a single name. 12. Haloalkanes also called A) Alkyl halides. B) Vinylic halides. C) All the above. D) None of the above. Show Answer Correct Answer: A) Alkyl halides. 13. The rate of reaction for SN$^{2 }$reactions is A) Rate = k [RX] [Nucleophile]. B) Rate= k[RX]. C) All the above. D) None of the above. Show Answer Correct Answer: A) Rate = k [RX] [Nucleophile]. 14. Which factor affects the reactivity of haloalkanes in nucleophilic substitution reactions? A) All of the above. B) The nature of the solvent used. C) The type of halogen present. D) The size of the alkyl group. Show Answer Correct Answer: A) All of the above. 15. Which of the following is a primary haloalkane? A) Chlorobutane. B) Pentane. C) Bromoethane. D) Iodopropane. Show Answer Correct Answer: C) Bromoethane. 16. In SN2 reactions the sequence of bond breaking and bond formation is as follows A) Nucleophile attacks the carbon from opposite side. B) The bond formation and bond breaking takes place simultaneously. C) The rate of reaction depends on the concentration of nucleophile. D) Sn2 mechanism is predominant in tertiary alkyl halide. Show Answer Correct Answer: B) The bond formation and bond breaking takes place simultaneously. 17. What ester is formed when ethanoic acid reacts with methanol? A) Propanoic ester. B) Methyl ethanoate. C) Ethyl methanoate. D) Methy ethyl ester. Show Answer Correct Answer: B) Methyl ethanoate. 18. What role does the solvent play in nucleophilic substitution reactions? A) The solvent changes the color of the reactants during the reaction. B) The solvent stabilizes the transition state and affects nucleophilicity. C) The solvent acts as a catalyst in the reaction. D) The solvent increases the reaction rate by providing heat. Show Answer Correct Answer: B) The solvent stabilizes the transition state and affects nucleophilicity. 19. Butanate nitrile can be prepared by heating A) Propyl chloride with KCN. B) Butyl alcohol with KCN. C) Butyl chloride with KCN. D) Propyl alcohol with KCN. Show Answer Correct Answer: A) Propyl chloride with KCN. 20. Triiodomethane has antiseptic property because of A) Formation of phosgene gas. B) Liberation of iodoform. C) Liberation of free iodine. D) None of these. Show Answer Correct Answer: C) Liberation of free iodine. 21. What are some common examples of haloalkanes? A) Isopropyl alcohol. B) Methyl acetate. C) Methyl chloride, ethyl bromide, isopropyl iodide. D) Ethyl alcohol. Show Answer Correct Answer: C) Methyl chloride, ethyl bromide, isopropyl iodide. 22. Consider the following s$_{N}$2 reactionsI. RX+Y$^{-}$ R-Y+X$^{-}$II. RX+Y R-Y$^{+}$+X$^{-}$III. RX$^{+}$+Y$^{-}$ R-Y+XIV. RX$^{+}$+Y R-Y$^{+}$+XIn which reactions there is large increase and large decrease n rate if reaction respectively with increase in polarity of the solvent? A) II&IV. B) II &III. C) I&IV. D) IV&I. Show Answer Correct Answer: B) II &III. 23. What are the reaction conditions for wurtz-fittig reaction? A) Na + aq.NaOH. B) Na in conc.HCl. C) Na + dry ether. D) Na in acidic medium. Show Answer Correct Answer: C) Na + dry ether. 24. Haloalkanes contains halogen atom(s) attached to the sp$^{3}$ hybridised carbon atom of an alkyl group. Identify haloalkane from the following compounds.(i) 2-Bromopentane(ii) Vinyl chloride(iii) 2-Chloroacetophenone(iv) Trichloromethane A) Only (i) and (iv). B) Only (ii) and (iv). C) (ii) only. D) Only (i), (ii) and (iii). Show Answer Correct Answer: A) Only (i) and (iv). 25. During Friedal crafts acetylation, the major product formed is A) P-Chloroacetophenone. B) O-chloroacetophenone. C) M-chloroacetophenone. D) Dichloroacetophenone. Show Answer Correct Answer: A) P-Chloroacetophenone. 26. The number of structural isomers of formula C$_{4}$H$_{9}$Br is ..... A) 2. B) 4. C) 3. D) 5. Show Answer Correct Answer: B) 4. 27. What determines the stereochemistry outcome of S N 2 reactions? A) Inversion. B) Retention. C) Racemization. D) No change. Show Answer Correct Answer: A) Inversion. 28. What is the rate dependency of S N 1 reactions? A) Zero order. B) Second order. C) Variable order. D) First order. Show Answer Correct Answer: D) First order. 29. What is the role of resonance in the reactivity of haloarenes? A) Halogens enhance the reactivity of haloarenes through resonance effects. B) Resonance stabilizes haloarenes but decreases their reactivity due to electron-withdrawing effects of halogens. C) Resonance has no effect on the stability or reactivity of haloarenes. D) Resonance increases the reactivity of haloarenes by stabilizing the negative charge. Show Answer Correct Answer: B) Resonance stabilizes haloarenes but decreases their reactivity due to electron-withdrawing effects of halogens. 30. What is the primary product when 1-bromopropane reacts with sodium hydroxide? A) Propanol. B) 1-bromopropane. C) Propane. D) Sodium bromide. Show Answer Correct Answer: A) Propanol. 31. What are the health effects associated with exposure to halogenated compounds? A) Enhanced skin health. B) Increased fertility rates. C) Improved respiratory function. D) Health effects include respiratory issues, skin irritation, endocrine disruption, carcinogenic potential, liver and kidney damage, neurological effects, and reproductive issues. Show Answer Correct Answer: D) Health effects include respiratory issues, skin irritation, endocrine disruption, carcinogenic potential, liver and kidney damage, neurological effects, and reproductive issues. 32. Ethylmagnesium chloride is an example of Grignard reagent. It may be used to prepare A) Ethanoic acid. B) 1-propanol. C) Ethanol. D) Ethene. Show Answer Correct Answer: B) 1-propanol. 33. Which haloalkane is commonly used as a refrigerant? A) Dichlorodifluoromethane (R-12). B) Trichlorofluoromethane (R-11). C) Chlorodifluoromethane (R-22). D) Bromochloromethane (R-20). Show Answer Correct Answer: A) Dichlorodifluoromethane (R-12). 34. The typical reaction of alkyl halide is: A) Electrophillic substitution. B) Nucleophillic substitution. C) Nucleophillic addition. D) Electrophillic addition. Show Answer Correct Answer: B) Nucleophillic substitution. 35. What is the effect of halogen substituents on the acidity of haloarenes? A) Halogen substituents increase the acidity of haloarenes. B) Halogen substituents decrease the acidity of haloarenes. C) Halogen substituents make haloarenes neutral in acidity. D) Halogen substituents have no effect on the acidity of haloarenes. Show Answer Correct Answer: A) Halogen substituents increase the acidity of haloarenes. 36. In the following sequence of reactionsCH$_{3}$CH$_{2}$CH$_{2}$Br+ (alc) KOH $\rightarrow$(A) + HBr $\rightarrow$ (B) + (aq) KOH $\rightarrow$ (C).The product (C) is A) Propan-2-ol. B) Propene. C) Propan-1-ol. D) Propyne. Show Answer Correct Answer: A) Propan-2-ol. 37. Grignard reagent, a very useful starting compound for a number of organic reactions can be prepared by A) Reaction of MgCl$_{2}$ with ether and alcohol. B) Reaction of alkyl halides with a solution of magnesium hydroxide. C) Reaction of alkyl halide with magnesium in presence of alcohol. D) Reaction of alkyl halides with dry magnesium powder in the presence of dry ether. Show Answer Correct Answer: D) Reaction of alkyl halides with dry magnesium powder in the presence of dry ether. 38. Which of the following compounds is the rate of alkaline hydrolysis that is independent of the concentration of the hydroxide ion? A) CH$_{3}$CH$_{2}$CH$_{2}$CH$_{2}$Cl. B) CH$_{3}$CH(Br)CH$_{3}$. C) C$_{6}$H$_{5}$CH$_{2}$CH$_{2}$I. D) (CH$_{3}$)$_{3}$CBr. Show Answer Correct Answer: D) (CH$_{3}$)$_{3}$CBr. 39. What is the rate dependency of S N 2 reactions? A) Second order. B) Zero order. C) First order. D) Variable order. Show Answer Correct Answer: A) Second order. 40. Name a method to convert haloalkanes to alkenes. A) Reduction using lithium aluminum hydride. B) Nucleophilic substitution with water. C) Elimination reaction using a strong base (e.g., KOH). D) Hydrogenation of haloalkanes. Show Answer Correct Answer: C) Elimination reaction using a strong base (e.g., KOH). 41. Which of the following undergoes nucleophilic substitution exclusively by SN1 mechanism? A) Benzyl chloride. B) Ethyl chloride. C) Isopropyl chloride. D) Choro benzene. Show Answer Correct Answer: A) Benzyl chloride. 42. Chloroform is kept in dark coloured bottles because A) It undergoes chlorination in transparent glass bottles. B) It starts burning when exposed to sunlight. C) It reacts with clear glass. D) It is oxidized to poisonous gas, phosgene in sunlight. Show Answer Correct Answer: D) It is oxidized to poisonous gas, phosgene in sunlight. 43. Which type of solvent favors S N 1 reactions? A) Ionic solvents. B) Polar protic solvents. C) Non-polar solvents. D) Polar aprotic solvents. Show Answer Correct Answer: B) Polar protic solvents. 44. How does the nature of the leaving group affect the mechanism of nucleophilic substitution? A) A better leaving group favors SN2 mechanisms over SN1. B) The leaving group does not influence the mechanism. C) Leaving groups only affect the rate of the reaction, not the mechanism. D) A better leaving group favors SN1 mechanisms over SN2. Show Answer Correct Answer: A) A better leaving group favors SN2 mechanisms over SN1. 45. Which statement is true about the C-X bond in alkyl halides? A) It has partial double bond character. B) It is purely covalent. C) It is polarized with carbon positive. D) It is purely ionic. Show Answer Correct Answer: C) It is polarized with carbon positive. 46. Arrange compound below according to decreasing boiling point;Pentane, 2-chloropropane, 1-butanol, 2-methylbutane A) 2-chloropropane, 2-methylbutane, Pentane, 1-butanol. B) 2-chloropropane, 1-butanol, 2-methylbutane, Pentane. C) 1-butanol, 2-chloropropane, Pentane, 2-methylbutane. D) 2-methylbutane, Pentane, 2-chloropropane, 1-butanol. Show Answer Correct Answer: C) 1-butanol, 2-chloropropane, Pentane, 2-methylbutane. 47. Explain the difference between primary, secondary, and tertiary haloalkanes. A) Tertiary haloalkanes have one carbon attached to the halogen. B) Primary haloalkanes have two carbons attached to the halogen. C) Primary haloalkanes have one carbon attached to the halogen, secondary have two, and tertiary have three. D) Secondary haloalkanes have three carbons attached to the halogen. Show Answer Correct Answer: C) Primary haloalkanes have one carbon attached to the halogen, secondary have two, and tertiary have three. 48. Toulene reacts with a halogen in the presence of iron(III) chloride giving ortho and para halo compounds. The reaction is A) Free radical addition reaction. B) Nucleophilic substitution reaction. C) Electrophilic elimination reaction. D) Electrophilic substitution reaction. Show Answer Correct Answer: D) Electrophilic substitution reaction. 49. An aryl chloride that helps in the treatment of typhoid fever is ..... A) Cholorobenzene. B) Chloroquine. C) Chloramphenicol. D) Chloroform. Show Answer Correct Answer: C) Chloramphenicol. 50. Test for 1-chlorobutane and 1-iodobutane A) Use silver nitrate, AgNO3$\rightarrow$ AgCl (white precipitate).$\rightarrow$ AgI (yellow ppt). B) Use silver nitrate, AgNO3$\rightarrow$ AgCl (yellow ppt).$\rightarrow$ AgI (white precipitate). C) All the above. D) None of the above. Show Answer Correct Answer: A) Use silver nitrate, AgNO3$\rightarrow$ AgCl (white precipitate).$\rightarrow$ AgI (yellow ppt). 51. Which of the following is not an allyclic halide? A) 3-Bromo-2-methylbut-1-ene. B) 4-Bromobut-1-ene. C) 1-Bromobut-2-ene. D) 4-Bromopent-2-ene. Show Answer Correct Answer: B) 4-Bromobut-1-ene. 52. Which alkyl halide has the highest reactivity for a particular alkyl group? A) R-F. B) R-Cl. C) R-Br. D) R-I. Show Answer Correct Answer: D) R-I. 53. CH$_{3}$CHCl$_{2}$ and CH$_{2}$Cl CH$_{2}$Cl are examples of: A) Position isomers. B) Functional isomers. C) Metamers. D) Chain isomers. Show Answer Correct Answer: A) Position isomers. 54. What is the main driving force for the nucleophilic substitution reaction of haloalkanes? A) Release of a leaving group. B) Polarization of the C-X bond. C) Formation of a stable carbocation. D) Formation of a double bond. Show Answer Correct Answer: A) Release of a leaving group. 55. Aryl halides are less reactive towards nucleophilic substitution due to: A) Resonance stabilization. B) Inductive effect. C) Smaller size of halogen. D) High polarity of C-X bond. Show Answer Correct Answer: A) Resonance stabilization. 56. Which type of solvent favors S N 2 reactions? A) Ionic solvents. B) Polar protic solvents. C) Non-polar solvents. D) Polar aprotic solvents. Show Answer Correct Answer: D) Polar aprotic solvents. 57. How does the presence of halogens affect the solubility of organic compounds? A) Halogens only increase the solubility of organic compounds in non-polar solvents. B) Halogens decrease the solubility of organic compounds in polar solvents. C) Halogens have no effect on the solubility of organic compounds. D) Halogens generally increase the solubility of organic compounds in polar solvents. Show Answer Correct Answer: D) Halogens generally increase the solubility of organic compounds in polar solvents. 58. In which type of nucleophilic substitution reaction does the nucleophile attack the substrate molecule in a single step? A) S N 1 reactions. B) S N 2 reactions. C) Both. D) None. Show Answer Correct Answer: B) S N 2 reactions. 59. Tertiary alkyl halides are are practically inert to substitution by SN2 BECAUSE OF A) Steric hindrance. B) Instability. C) Inductive effect. D) Insolubility. Show Answer Correct Answer: A) Steric hindrance. 60. How are haloalkanes used in refrigeration? A) Haloalkanes are used as refrigerants in refrigeration systems. B) Haloalkanes are utilized in the production of plastics. C) Haloalkanes are used as solvents in paint. D) Haloalkanes are primarily used as fuels in engines. Show Answer Correct Answer: A) Haloalkanes are used as refrigerants in refrigeration systems. ← PreviousNext →Related QuizzesScience QuizzesClass 12 QuizzesClass 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 1Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 3Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 4Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 5Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 6Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 7Class 12 Chemistry (Part Ii) Chapter 11 Alcohols QuizClass 12 Chemistry (Part Ii) Chapter 12 Aldehydes Quiz 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books