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 7 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 7 (56 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. In a SN1 reaction on chiral centres, there is A) 100% retention. B) 100% inversion. C) Racemization. D) None. Show Answer Correct Answer: C) Racemization. 2. Which of the following haloalkanes reacts with aqueous KOH most easily? A) 2-chlorobutane. B) 2-bromobutane. C) 2-bromo-2-methylpropane. D) 1-bromobutane. Show Answer Correct Answer: C) 2-bromo-2-methylpropane. 3. Haloalkane is a polar molecule that undergoes nucleophilic substitution through S$_{N}$1 and S$_{N}$2. Arrange the following haloalkanes in order of increasing rate of unimolecular nucleophilic substitution reaction:I. 2-chloro-2-methylpropaneII. 2-chlorobutaneIII. 1-chlorobutane A) I< III < II. B) III< I < II. C) I< II < III. D) III< II < I. Show Answer Correct Answer: D) III< II < I. 4. Which of the following reactions can be used to fluorinate a compound? A) Sandmeyer's reaction. B) Darzen's reaction. C) Hunsdicker reaction. D) Swartz reaction. Show Answer Correct Answer: D) Swartz reaction. 5. Which halogen has the highest electronegativity in haloalkanes and haloarenes? A) Iodine. B) Fluorine. C) Chlorine. D) Bromine. Show Answer Correct Answer: B) Fluorine. 6. In two separate experiments equal quantities of an alkyl halide C$_{4}$H$_{9}$Cl, were treated at the same temperature with equal volume of 0.1 molar and 0.2 molar solution of NaOH respectively. In both the experiments t$_{1/2}$ of the two reactio were the same. The most likely structure of halide is A) (CH$_{3}$)$_{3}$CCl. B) CH$_{3}$CH$_{2}$CH$_{2}$CH$_{2}$Cl. C) CH$_{3}$CH(Cl)CH$_{2}$CH$_{3}$. D) (CH$_{3}$)$_{2}$CHCH$_{2}$Cl. Show Answer Correct Answer: A) (CH$_{3}$)$_{3}$CCl. 7. Which of the haloalkanes is most likely to undergo substitution reactions? A) Alkyl bromides. B) Alkyl iodides. C) Alkyl chlorides. D) Alkyl fluorides. Show Answer Correct Answer: B) Alkyl iodides. 8. A primary alkyl halide would prefer to undergo ..... A) SN2 reaction. B) SN1 reaction. C) Racemisation. D) $\alpha$-Elimination. Show Answer Correct Answer: A) SN2 reaction. 9. OF 1, 1, 2, 2-tetrachloropropane was heated with Zn dust and the product was bubbled through ammoniacal AgNO$_{3}$. What is the weight of precipitate obtained? A) 29.4g. B) 28.0g. C) 25.7g. D) 30.0g. Show Answer Correct Answer: A) 29.4g. 10. Which of the following reactions follows Markovnikov's rule? A) C$_{3}$H$_{6}$+Cl$_{2}$. B) C$_{2}$H$_{4}$+HBr. C) C$_{3}$H$_{6}$+HBr. D) C$_{3}$H$_{6}$+Br$_{2}$. Show Answer Correct Answer: C) C$_{3}$H$_{6}$+HBr. 11. Haloalkanes are best obtained by A) Swartz reaction. B) Darzzen's process. C) Finkelstein process. D) None of these. Show Answer Correct Answer: B) Darzzen's process. 12. The hybridisation of carbon in diamond is A) Sp. B) Dsp2. C) Sp3. D) Sp2. Show Answer Correct Answer: C) Sp3. 13. What type of reaction do haloarenes typically undergo? A) Addition reaction. B) Decomposition reaction. C) Nucleophilic substitution. D) Electrophilic aromatic substitution. Show Answer Correct Answer: D) Electrophilic aromatic substitution. 14. Of an organic halide (A) when dissolved in 2.0g of camphor, the melting point of the mixture was found to be 167 . Compound(A) when heated with Na gives a gas (B). 280ml of gas (B) at STP weighs 0.375g. What would be A in the whole process? (K$_{f}$ for camphor =40, m.pt of camphor=179 ). A) C$_{3}$H$_{7}$Br. B) C$_{2}$H$_{5}$Br. C) CH$_{3}$I. D) (CH$_{3}$)$_{2}$CHI. Show Answer Correct Answer: C) CH$_{3}$I. 15. What is the product from heating a secondary alcohol under reflux? A) Aldehyde. B) Carboxylic acid. C) Ketone. D) Tertiary alcohol. Show Answer Correct Answer: C) Ketone. 16. Toluene 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) Electrophilic substitution reaction. C) Electrophilic elimination reaction. D) Nucleophilic substitution reaction. Show Answer Correct Answer: B) Electrophilic substitution reaction. 17. Which hybridization is absent in haloarenes? A) Sp3. B) Sp. C) Sp2. D) Sp3d. Show Answer Correct Answer: A) Sp3. 18. What is the role of Grignard reagents in the synthesis of complex molecules in the pharmaceutical and chemical industry? A) Catalysts. B) Inhibitors. C) Solvents. D) Building blocks. Show Answer Correct Answer: D) Building blocks. 19. Why Grignard reagent always prepared in anhydrous condition? A) Because it can extract hydrogen from R-X to hydrocarbon. B) Because it can extract hydrogen from H2O to Alkene. C) Because it can extract hydrogen even from H2O to hydrocarbon. D) None. Show Answer Correct Answer: C) Because it can extract hydrogen even from H2O to hydrocarbon. 20. Butane nitrile can be prepared by heating A) Butyl chloride with KCN. B) Butyl alcohol with KCN. C) Propyl alcohol with KCN. D) Propyl chloride with KCN. Show Answer Correct Answer: D) Propyl chloride with KCN. 21. List two physical properties of haloarenes that distinguish them from haloalkanes. A) Lower boiling points than haloalkanes. B) Generally more polar than haloalkanes. C) 1. Higher boiling points than haloalkanes. 2. Generally less polar than haloalkanes. D) Higher solubility in water than haloalkanes. Show Answer Correct Answer: C) 1. Higher boiling points than haloalkanes. 2. Generally less polar than haloalkanes. 22. Which of the following haloalkanes is the most reactive towards nucleophilic substitution? A) CH3I. B) CH3F. C) CH3Cl. D) CH3Br. Show Answer Correct Answer: A) CH3I. 23. The position of-Br in the compound in CH3CH=CHC(Br)(CH3)2 can be classified as ..... A) Allyl. B) Aryl. C) Vinyl. D) Secondary. Show Answer Correct Answer: A) Allyl. 24. Complete the following reaction 3R-OH + PCl3 $\rightarrow$ A) H2PO2. B) H3PO5. C) H3PO4. D) H3PO3. Show Answer Correct Answer: D) H3PO3. 25. Reaction of C$_{6}$H$_{5}$CH$_{2}$Br with aqueous solution hydroxide follows ..... A) S$_{N}$1 mechanism. B) S$_{N}$2 mechanism. C) Any of the two above depending upon the temperature of reaction. D) Satyzeff rule. Show Answer Correct Answer: A) S$_{N}$1 mechanism. 26. How does steric hindrance affect SN2 reactions? A) Steric hindrance only affects SN1 reactions. B) Steric hindrance has no effect on SN2 reactions. C) Steric hindrance decreases the rate of SN2 reactions. D) Steric hindrance increases the rate of SN2 reactions. Show Answer Correct Answer: C) Steric hindrance decreases the rate of SN2 reactions. 27. Benzyl chloride (C$_{6}$H$_{5}$CH$_{2}$Cl) can be prepared from toluene by chlorination With A) Cl$_{2 }$ /Fe. B) Cl$_{2 }$/hv. C) SO$_{2}$Cl$_{2}$. D) NaOCl. Show Answer Correct Answer: B) Cl$_{2 }$/hv. 28. What are the physical properties that distinguish haloalkanes from alkanes? A) Haloalkanes are more soluble in water than alkanes. B) Haloalkanes have higher boiling points, greater polarity, and different solubility compared to alkanes. C) Haloalkanes have lower boiling points than alkanes. D) Haloalkanes are less polar than alkanes. Show Answer Correct Answer: B) Haloalkanes have higher boiling points, greater polarity, and different solubility compared to alkanes. 29. For a given halogen atom the reactivity is maximum for A) Secondary halide. B) Methyl halide. C) Tertiary halide. D) Primary halide. Show Answer Correct Answer: C) Tertiary halide. 30. Assertion:Haloalkanes undergo nucleophilic substitution reactions. Reason:The carbon atom in haloalkanes is electrophilic due to the presence of a halogen. A) Both the assertion and reason are correct. B) Haloalkanes do not undergo nucleophilic substitution reactions. C) Both the assertion and reason are incorrect. D) The carbon atom in haloalkanes is nucleophilic due to the presence of a halogen. Show Answer Correct Answer: A) Both the assertion and reason are correct. 31. Which statements are true about the characteristics of a fluoroalkane?1 It is less reactive than chloroalkane2 It is not easily flammable 3 It can be used as aerosol propellant A) 2 & 3 only are correct. B) 1, 2 & 3 are correct. C) 1 only is correct. D) 1 & 2 only are correct. Show Answer Correct Answer: B) 1, 2 & 3 are correct. 32. Tertiary alkyl halide are practically inert to substitution by SN2 mechanism A) The rate of reaction is faster in SN2 mechanism. B) There is inductive effect. C) There is steric hindrance. D) Carbocation formed is unstable. Show Answer Correct Answer: C) There is steric hindrance. 33. Chlorobenzene on treatment with Na in dry ether gives diphenyl. The name of the reaction is A) Wurtz-Fittig reaction. B) Gattermann reaction. C) Fittig reaction. D) Sandmeyer reaction. Show Answer Correct Answer: C) Fittig reaction. 34. Mechanism for hydrolysis of iodoethane to ethanol by aqueous NaOH A) S$_{N}$2. B) S$_{N}$1. C) All the above. D) None of the above. Show Answer Correct Answer: A) S$_{N}$2. 35. Which of the following compounds can yield only one monochlorinated product upon free radical chlorination? A) 2, 2-dimethylpropane. B) N-butane. C) 2-methylbutane. D) 2-methylpropane. Show Answer Correct Answer: A) 2, 2-dimethylpropane. 36. Assertion:The presence of halogens in haloarenes makes them more polar than benzene. Reason:Halogens are electronegative and withdraw electron density from the aromatic ring. A) True. B) Halogens do not affect the polarity of benzene. C) Benzene is more polar than haloarenes due to its structure. D) Halogens increase the electron density of the aromatic ring. Show Answer Correct Answer: A) True. 37. Assertion:Haloarenes can be synthesized from phenols by halogenation. Reason:This reaction involves the substitution of a hydrogen atom with a halogen atom. A) Haloarenes cannot be synthesized from phenols. B) The reaction involves the addition of a halogen atom, not substitution. C) Phenols are not involved in the synthesis of haloarenes. D) Both the assertion and reason are true, and the reason correctly explains the assertion. Show Answer Correct Answer: D) Both the assertion and reason are true, and the reason correctly explains the assertion. 38. Discuss the stability of carbocations in haloalkane reactions. A) Primary carbocations are more stable than tertiary carbocations. B) Tertiary carbocations are the most stable, followed by secondary, primary, and methyl carbocations. C) Methyl carbocations are the most stable, followed by primary, secondary, and tertiary. D) Secondary carbocations are the least stable, followed by primary, tertiary, and methyl. Show Answer Correct Answer: B) Tertiary carbocations are the most stable, followed by secondary, primary, and methyl carbocations. 39. If no bond around the stereocenter is broken the product is said to have A) Inversion of configuration. B) Retention of configuration. C) All the above. D) None of the above. Show Answer Correct Answer: B) Retention of configuration. 40. What is the reactivity of haloarenes compared to haloalkanes? A) More reactive. B) Less reactive. C) Equally reactive. D) Not reactive. Show Answer Correct Answer: B) Less reactive. 41. Give an example of a nucleophile used in SN2 reactions. A) Chloride ion (Cl-). B) Bromide ion (Br-). C) Sodium ion (Na+). D) Hydroxide ion (OH-). Show Answer Correct Answer: D) Hydroxide ion (OH-). 42. Is haloalkane polar or non polar? A) Polar molecules. B) Non polar molecules. C) All the above. D) None of the above. Show Answer Correct Answer: A) Polar molecules. 43. Which compound do not have sec. carbon? A) 2-Clorobutane. B) Ethanol. C) Butane. D) Phenol. Show Answer Correct Answer: B) Ethanol. 44. Which of the following is a method of preparing haloalkanes from alcohols? A) Nucleophilic substitution. B) Electrophilic substitution. C) Hydrolysis. D) Free radical halogenation. Show Answer Correct Answer: A) Nucleophilic substitution. 45. Which of the following alkyl halides is hydrolysed by S$_{N}$1 mechanism? A) (CH$_{3}$)$_{3}$CCl. B) CH$_{3}$CH$_{2}$Cl. C) CH$_{3}$CH$_{2}$CH$_{2}$Cl. D) CH$_{3}$Cl. Show Answer Correct Answer: A) (CH$_{3}$)$_{3}$CCl. 46. What type of nucleophiles are typically used in SN1 reactions? A) Weak nucleophiles such as water or alcohols. B) Strong nucleophiles like hydroxide ions. C) Charged nucleophiles such as amines. D) Nucleophiles that are highly reactive and unstable. Show Answer Correct Answer: A) Weak nucleophiles such as water or alcohols. 47. 2-Bromo-3, 3-dimethylbutane on reaction with aqueous KOH yields X as the major product. X is A) 2, 2-dimethybutan-3-ol. B) 2, 2-dimethylpropan-2-ol. C) 2, 3, 3-trimethylpropan-1-ol. D) 2, 3-dimethylbutan-2-ol. Show Answer Correct Answer: D) 2, 3-dimethylbutan-2-ol. 48. Complete the following reaction R-OH + PCl5 $\rightarrow$ A) PCl5. B) POCl3. C) PCl3. D) POBr3. Show Answer Correct Answer: B) POCl3. 49. An alkyl chloride produces a single alkene on reaction with sodium ethoxide and ethanol. The alkene further undergoes hydrogenation to yield 2-methylbutane. Identify the alkyl chloride amongst the following compounds. A) ClCH$_{2}$CH(CH$_{3}$)CH$_{2}$CH$_{3}$. B) ClCH$_{2}$CH(CH$_{3}$)CH$_{2}$CH$_{3}$. C) CH$_{3}$C(Cl)(CH$_{3}$)CH$_{2}$CH$_{3}$. D) ClCH$_{2}$CH$_{2}$CH$_{2}$CH$_{3}$. Show Answer Correct Answer: A) ClCH$_{2}$CH(CH$_{3}$)CH$_{2}$CH$_{3}$. 50. Alkenes react with hydrogen halides, HX to formed haloalkane. In the reaction;I. the pi electrons are used to form a bond with the hydrogen atom from HXII. the intermediate product is carbocationIII. the rate of reaction increases in the order:HF, HCl, HBr, HI A) I only. B) I and II only. C) II and III only. D) I, II and III. Show Answer Correct Answer: D) I, II and III. 51. What is the stereochemistry outcome of S N 1 reactions? A) Racemization reactions. B) No change in stereochemistry. C) Inversion reactions. D) Retain stereochemistry. Show Answer Correct Answer: A) Racemization reactions. 52. Name the haloalkane:CH3CH2CH2CH2CH2CH2CH2Br A) 1-bromohexene. B) 1-bromohexyne. C) 1-bromohexane. D) 1-bromopentane. Show Answer Correct Answer: C) 1-bromohexane. 53. Which of the following is a chiral molecule? A) CH$_{3}$CHBrCH$_{2}$CH$_{3}$. B) CH$_{3}$CBr$_{2}$Cl. C) (CH$_{3}$)$_{2}$CHCl. D) CH$_{2}$BrI. Show Answer Correct Answer: A) CH$_{3}$CHBrCH$_{2}$CH$_{3}$. 54. Which of the following is a characteristic property of haloalkanes? A) Presence of carbon-halogen bonds. B) Presence of hydroxyl groups. C) Presence of double bonds. D) Presence of carbon-carbon bonds. Show Answer Correct Answer: A) Presence of carbon-halogen bonds. 55. In SN$^{1}$ type of mechanism the intermediate species is: A) A free radical. B) A carbonium ion(carbo cation). C) A carboanion. D) None of these. Show Answer Correct Answer: B) A carbonium ion(carbo cation). 56. Which of the following will have maximum boiling point? A) C$_{3}$H$_{7}$Br. B) C$_{3}$H$_{7}$I. C) C$_{3}$H$_{7}$Cl. D) C$_{3}$H$_{7}$F. Show Answer Correct Answer: B) C$_{3}$H$_{7}$I. ← PreviousRelated 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 2Class 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 11 Alcohols QuizClass 12 Chemistry (Part Ii) Chapter 12 Aldehydes Quiz 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books