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 6 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 6 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. How does the presence of halogens affect the acidity of haloarenes? A) Halogens have no effect on the acidity of haloarenes. B) Halogens increase the acidity of haloarenes by stabilizing the conjugate base. C) Halogens decrease the acidity of haloarenes by destabilizing the conjugate base. D) Halogens increase the acidity of haloarenes by forming stronger bonds with hydrogen. Show Answer Correct Answer: B) Halogens increase the acidity of haloarenes by stabilizing the conjugate base. 2. Assertion (A):Presence of nitro group at ortho or para position increases the reactivity of haloarenes towards nucleophilic substitution reaction.Reason (R):Nitro group being an electron withdrawing group decreases the electron density over the benzene ring. A) Both A and R are correct; R is the correct explanation of A. B) Both A and R are correct; R is not the correct explanation of A. C) A is correct; R is incorrect. D) A is incorrect; R is correct. Show Answer Correct Answer: A) Both A and R are correct; R is the correct explanation of A. 3. S$_{N}$2 mechanism favor A) Methyl halide. B) 3$^\circ$ haloalkane. C) All the above. D) None of the above. Show Answer Correct Answer: A) Methyl halide. 4. Assertion:Haloalkanes can be prepared by the reaction of alcohols with hydrogen halides. Reason:This reaction is known as halogenation. A) Assertion is false, Reason is true. B) Both Assertion and Reason are true. C) Both Assertion and Reason are false. D) Assertion is true, Reason is false. Show Answer Correct Answer: D) Assertion is true, Reason is false. 5. Iodoform can be prepared from all except A) Isopropyl alcohol. B) 3-methyl-3-butanone. C) Ethylmethyl ketone. D) Isobutyl alcohol. Show Answer Correct Answer: D) Isobutyl alcohol. 6. Which of the following cannot be prepared by the Wurtz reaction? A) Methane. B) Ethane. C) Propane. D) N-Butane. Show Answer Correct Answer: A) Methane. 7. What is the role of a catalyst in electrophilic aromatic substitution? A) A catalyst acts as a nucleophile in the reaction. B) A catalyst increases the reactivity of the electrophile in electrophilic aromatic substitution. C) A catalyst is not necessary for electrophilic aromatic substitution. D) A catalyst decreases the stability of the aromatic ring. Show Answer Correct Answer: B) A catalyst increases the reactivity of the electrophile in electrophilic aromatic substitution. 8. Assertion:The preparation of haloalkanes can also be achieved through the reaction of alkenes with halogens. Reason:This is known as halogenation of alkenes. A) The reaction of alkenes with halogens is called hydrogenation. B) Halogenation involves the reaction of haloalkanes with alkenes. C) True. D) Haloalkanes cannot be prepared from alkenes. Show Answer Correct Answer: C) True. 9. Alkyl halide on treatment with aqueous KOH give A) Alcohols. B) Acids. C) Alkanes. D) Aldehydes. Show Answer Correct Answer: A) Alcohols. 10. Which of the following halogenated compounds is most commonly used as a refrigerant? A) Chlorofluorocarbon (CFC). B) All of the above. C) Hydrochlorofluorocarbon (HCFC). D) Perfluorocarbon (PFC). Show Answer Correct Answer: B) All of the above. 11. What is the primary reaction type that haloalkanes undergo with nucleophiles? A) Addition reaction. B) Elimination reaction. C) Nucleophilic substitution. D) Redox reaction. Show Answer Correct Answer: C) Nucleophilic substitution. 12. The reaction:R-Cl + KI $\rightarrow$ RI + KCl (in presence of acetone)Is known as A) Ulmann reaction. B) Hunsdieker reaction. C) Wurtz reaction. D) Finkelstein reaction. Show Answer Correct Answer: D) Finkelstein reaction. 13. S$_{N}$1 mechanism favor A) 3$^\circ$ haloalkane. B) 1$^\circ$ haloalkane. C) All the above. D) None of the above. Show Answer Correct Answer: A) 3$^\circ$ haloalkane. 14. How do you classify haloalkanes based on the carbon atom to which the halogen is attached? A) Haloalkanes are classified as primary, secondary, or tertiary based on the carbon atom to which the halogen is attached. B) Haloalkanes are classified by their boiling points. C) Haloalkanes are classified based on the number of hydrogen atoms. D) Haloalkanes are classified as aromatic or aliphatic. Show Answer Correct Answer: A) Haloalkanes are classified as primary, secondary, or tertiary based on the carbon atom to which the halogen is attached. 15. Which of the following is a feature of the Sn1 reaction mechanism? A) It involves a single step. B) It forms a carbocation intermediate. C) It is favored by polar aprotic solvents. D) It occurs with primary haloalkanes only. Show Answer Correct Answer: B) It forms a carbocation intermediate. 16. Assertion:Haloalkanes are generally more soluble in water than haloarenes. Reason:Haloalkanes can form hydrogen bonds with water molecules. A) Haloarenes are more soluble in water than haloalkanes. B) False. C) Haloalkanes are less soluble in water than haloarenes. D) Haloalkanes cannot form hydrogen bonds with water molecules. Show Answer Correct Answer: B) False. 17. Which reagent is commonly used to convert haloalkanes into alcohols? A) NaOH (dry). B) H2O. C) KOH (aq). D) NaBH4. Show Answer Correct Answer: C) KOH (aq). 18. The reaction:CH$_{3}$Br + AgF $\rightarrow$ CH$_{3}$F + AgBr is called A) Swarts reaction. B) Finkelstein reaction. C) Perkin reaction. D) Gattermann reaction. Show Answer Correct Answer: A) Swarts reaction. 19. What type of bond is present in haloalkanes? A) Hydrogen bond. B) Metallic bond. C) Ionic bond. D) Covalent bond. Show Answer Correct Answer: D) Covalent bond. 20. How can aryl halides be prepared from diazonium salts? A) By reacting the diazonium salt with a strong acid. B) By heating the diazonium salt with a reducing agent. C) By mixing the diazonium salt with an alkali metal. D) By treating the diazonium salt with a copper(I) halide (CuX) in the presence of a base. Show Answer Correct Answer: D) By treating the diazonium salt with a copper(I) halide (CuX) in the presence of a base. 21. How do you name a haloarene with a bromine substituent on a benzene ring? A) Bromobenzene. B) Benzene-bromo. C) Bromo-benzene. D) Bromo benzene or-bromobenzene. Show Answer Correct Answer: D) Bromo benzene or-bromobenzene. 22. Which of the following alkyl halides will undergoes S$_{N}$1 reaction most readily? A) (CH$_{3}$)$_{3}$C-I. B) (CH$_{3}$)$_{3}$C-F. C) (CH$_{3}$)$_{3}$C-Br. D) (CH$_{3}$)$_{3}$C-Cl. Show Answer Correct Answer: A) (CH$_{3}$)$_{3}$C-I. 23. Assertion:PCl3 &PCl5 are preferred over thionyl chloride for the preparation of alkylchloride from alcoholsReason:Phosphorous chlorides give pure alkyl halides A) A and R are correct statements, and R is the correct explanation of A. B) A and R are correct statements, but R is not the correct explanation of A. C) A is correct, B is incorrect statements. D) A is incorrect, R is correct statement. Show Answer Correct Answer: B) A and R are correct statements, but R is not the correct explanation of A. 24. Dichloroethane and 1, 2-dichloroethane are structural isomers. What are the products formed when both isomers are hydrolysed separately in dilute hydrochloric acid? A) HOCH$_{2}$CH$_{2}$OH and CH$_{3}$CHO. B) HOCH$_{2}$CH$_{2}$OH and CH$_{3}$CH(OH)$_{2}$. C) HOCH$_{2}$CH$_{2}$Cl and CH$_{3}$CHO. D) HOCH$_{2}$CH$_{2}$OH and CH$_{3}$CH(OH)Cl. Show Answer Correct Answer: A) HOCH$_{2}$CH$_{2}$OH and CH$_{3}$CHO. 25. What are haloarenes and how do they differ from haloalkanes? A) Haloarenes are non-aromatic compounds with halogen atoms. B) Haloalkanes contain only carbon and hydrogen without halogens. C) Haloarenes are aromatic compounds with halogen atoms attached to an aromatic ring, while haloalkanes are aliphatic compounds with halogen atoms attached to carbon atoms. D) Haloarenes are saturated compounds with halogen atoms. Show Answer Correct Answer: C) Haloarenes are aromatic compounds with halogen atoms attached to an aromatic ring, while haloalkanes are aliphatic compounds with halogen atoms attached to carbon atoms. 26. Which type of carbon atom in haloalkanes is sp3 hybridized? A) Vinylic carbon. B) Allylic carbon. C) Alkyl carbon. D) Aromatic carbon. Show Answer Correct Answer: C) Alkyl carbon. 27. Give an example of a reagent commonly used in the preparation of alkyl halides from alcohols. A) Sulfuric acid (H2SO4). B) Nitric acid (HNO3). C) Acetic acid (CH3COOH). D) Hydrochloric acid (HCl). Show Answer Correct Answer: D) Hydrochloric acid (HCl). 28. What is the impact of solvent polarity on the rate of SN1 and SN2 reactions? A) Polar protic solvents favor SN1 reactions, while polar aprotic solvents favor SN2 reactions. B) Solvent polarity has no effect on the rate of nucleophilic substitution reactions. C) Polar solvents increase the rate of both SN1 and SN2 reactions. D) Non-polar solvents are preferred for both SN1 and SN2 reactions. Show Answer Correct Answer: A) Polar protic solvents favor SN1 reactions, while polar aprotic solvents favor SN2 reactions. 29. A Grignard reagent may be made by reacting magnesium with A) Ethyl alcohol. B) Methyl amine. C) Ethyl iodide. D) Diethyl ether. Show Answer Correct Answer: C) Ethyl iodide. 30. What is the IUPAC name for CH3Cl? A) Chloromethane. B) Methyl chloride. C) Chloroethane. D) Methanol. Show Answer Correct Answer: A) Chloromethane. 31. How does the leaving group affect the rate of nucleophilic substitution? A) A worse leaving group increases the rate of nucleophilic substitution. B) A better leaving group decreases the rate of nucleophilic substitution. C) The leaving group has no effect on the rate of nucleophilic substitution. D) A better leaving group increases the rate of nucleophilic substitution. Show Answer Correct Answer: D) A better leaving group increases the rate of nucleophilic substitution. 32. An alkyl halide with molecular formula, C$_{6}$H$_{5}$Br on dehydrohalogenation gives two isomeric alkenes X and Y with molecular formula, C$_{6}$H$_{12}$. On reductive ozonolysis X and Y gave four compounds CH$_{3}$COCH$_{3}$, CH$_{3}$CHO, CH$_{3}$CH$_{2}$CHO and (CH$_{3}$)$_{2}$CHCHO. The alkyl halide is A) 2-bomo-2, 3-dimethylbutane. B) 4-bromo-2-methylpentane. C) 3-bromo-2-methylpentane. D) 2, 2-dimethyl-1-bromobutane. Show Answer Correct Answer: C) 3-bromo-2-methylpentane. 33. The product when R-X react with grignard reagent (Mg/ dry ether): A) RMgX. B) Mg-X. C) R-H (alkane). D) R-X. Show Answer Correct Answer: A) RMgX. 34. In S$_{N}$2 reaction the sequence of bond breaking and bond formation is as follows A) Bond breaking and formation take place randomly. B) Bond formation is followed by breaking. C) Bond breaking followed by formation. D) Bond breaking and formation occur simultaneously. Show Answer Correct Answer: D) Bond breaking and formation occur simultaneously. 35. Assertion:The boiling points of haloalkanes increase with increasing molecular weight. Reason:This is due to increased van der Waals forces in larger molecules. A) The assertion is false, but the reason is true. B) The assertion is true, but the reason is false. C) Both the assertion and reason are true, and the reason correctly explains the assertion. D) Both the assertion and reason are false. Show Answer Correct Answer: C) Both the assertion and reason are true, and the reason correctly explains the assertion. 36. Which of the following is obtained by the reaction of chlorobenzene with ammonia under high pressure and temperature? A) Phenol. B) Aniline. C) Benzamide. D) Nitrobenzene. Show Answer Correct Answer: B) Aniline. 37. During the course of SN1 reaction, the intermediate species formed is A) An intermediate. B) A carbocation. C) A free radical. D) A carbanion. Show Answer Correct Answer: B) A carbocation. 38. Elimination of bromine from 2-bromobutane result in the formation of A) Predominantly 2-butene. B) Predominantly 2-butyne. C) Equimolar mixture of 1 and 2-butene. D) Predominantly 1-butene. Show Answer Correct Answer: A) Predominantly 2-butene. 39. SN$^{2}$ reaction involves the formation of ..... intermediate A) Carbocation. B) Carboanion. C) Transition state. D) None of these. Show Answer Correct Answer: C) Transition state. 40. What is a racemic mixture? A) Mixture of chiral molecules. B) Mixture of dextro & laevo enantiomers. C) Mixture of 2 dextro enantiomers. D) Mixture of 2 laevo enantiomers. Show Answer Correct Answer: B) Mixture of dextro & laevo enantiomers. 41. The number of isomers (including structural and stereoisomers) of C$_{4}$H$_{9}$Cl is A) 5. B) 3. C) 2. D) 4. Show Answer Correct Answer: A) 5. 42. When an alkyl halide reacts with alcoholic KOH, the major product is: A) Halogen exchange compound. B) Ether. C) Alkene. D) Alcohol. Show Answer Correct Answer: C) Alkene. 43. Methyl bromide reacts with AgF to give methylflouride and silver bromide. This reaction is called A) Swarts reaction. B) Fittig reaction. C) Finkelstein reaction. D) Wurtz reaction. Show Answer Correct Answer: A) Swarts reaction. 44. What are the common methods for synthesizing haloarenes? A) Hydrogenation of aryl compounds. B) Friedel-Crafts acylation. C) Common methods for synthesizing haloarenes include electrophilic aromatic substitution, Sandmeyer reaction, and nucleophilic aromatic substitution. D) Grignard reaction. Show Answer Correct Answer: C) Common methods for synthesizing haloarenes include electrophilic aromatic substitution, Sandmeyer reaction, and nucleophilic aromatic substitution. 45. Good conductor of electricity and heat is A) Anthracite cake. B) Diamond. C) Graphite. D) Charcoal. Show Answer Correct Answer: C) Graphite. 46. In a molecule of tertiary haloalkanes, carbon atom is bonded to A) 2 carbon atoms. B) 1 carbon atom. C) 4 carbon atoms. D) 3 carbon atoms. Show Answer Correct Answer: D) 3 carbon atoms. 47. What type of reaction do haloalkanes typically undergo with nucleophiles? A) Radical substitution. B) Elimination reaction. C) Nucleophilic substitution. D) Electrophilic addition. Show Answer Correct Answer: C) Nucleophilic substitution. 48. What is the significance of ortho and para positions in haloarenes? A) The ortho and para positions are less reactive due to steric hindrance. B) The ortho and para positions in haloarenes are more reactive for electrophilic substitution due to stabilization of the carbocation intermediate. C) Electrophilic substitution is favored at the meta position in haloarenes. D) The ortho and para positions are only relevant in aliphatic compounds. Show Answer Correct Answer: B) The ortho and para positions in haloarenes are more reactive for electrophilic substitution due to stabilization of the carbocation intermediate. 49. What is the difference between SN1 and SN2 mechanisms in nucleophilic substitution reactions? A) The main difference between SN1 and SN2 mechanisms is the number of steps involved and the nature of the transition state. B) SN1 reactions are faster than SN2 reactions. C) SN1 involves a concerted mechanism while SN2 involves stepwise mechanism. D) The difference lies in the type of nucleophile used. Show Answer Correct Answer: A) The main difference between SN1 and SN2 mechanisms is the number of steps involved and the nature of the transition state. 50. Which of the following is most reactive towards aqueous NaOH? A) C$_{6}$H$_{5}$Br. B) C$_{6}$H$_{5}$CH$_{2}$Cl. C) BrC$_{6}$H$_{4}$Br. D) C$_{6}$H$_{5}$Cl. Show Answer Correct Answer: B) C$_{6}$H$_{5}$CH$_{2}$Cl. 51. Name the pesticide whose resistance was developed by many organisms and banned in some countries?? A) Cholroform. B) Freons. C) Dicholoro-diphenyl-tricholroethane. D) Dicholro-diphenylether. Show Answer Correct Answer: C) Dicholoro-diphenyl-tricholroethane. 52. What causes the dipole moment in haloalkanes and haloarenes? A) The polarity of the C-X bond. B) The size of the halogen atom. C) The hybridization of carbon. D) The reactivity of the compound. Show Answer Correct Answer: A) The polarity of the C-X bond. 53. Reactions involving grignard reagents reaction with CO2 A) RMgX + CO2 + H2O $\rightarrow$ RCOOH + Mg(OH)X. B) RMgX + CO2 + H2O $\rightarrow$ ROH + Mg(OH)X. C) All the above. D) None of the above. Show Answer Correct Answer: A) RMgX + CO2 + H2O $\rightarrow$ RCOOH + Mg(OH)X. 54. The solution used to distinguish chloroform and iodoform is A) Silver nitrate solution. B) Sodium iodide. C) Silver chloride solution. D) None of the above. Show Answer Correct Answer: A) Silver nitrate solution. 55. Iodoalkanes are prepared from chloro or bromoalkane using ..... and the name of the reaction is ..... A) NaI, SWARTS. B) NaI, FINKELSTEIN. C) AgI, SWARTS. D) None of the above. Show Answer Correct Answer: B) NaI, FINKELSTEIN. 56. What is the hybridization of carbon in haloarenes? A) Sp2. B) Sp3d. C) Sp. D) Sp3. Show Answer Correct Answer: A) Sp2. 57. Alkyl halides are formed when thionyl chloride and ..... are refluxed in presence of pyridine.The order of reactivity (3$^{0}$>2$^{0}$>1$^{0}$) is due to +1 effect of the alkyl group which ..... the polarity of C-X bond. A) Acids, decreases. B) Aldehydes, changes. C) Ketones, decreases. D) Alcohols, increases. Show Answer Correct Answer: D) Alcohols, increases. 58. Explain the role of haloalkanes in organic synthesis. A) Haloalkanes are stable compounds that do not participate in any chemical reactions. B) Haloalkanes are key intermediates in organic synthesis, enabling the formation of various functional groups through nucleophilic reactions. C) Haloalkanes are primarily used as solvents in organic reactions. D) Haloalkanes are only used in polymer production and have no role in organic synthesis. Show Answer Correct Answer: B) Haloalkanes are key intermediates in organic synthesis, enabling the formation of various functional groups through nucleophilic reactions. 59. Name the reaction which yields alkyl flourides A) Finkelstein reaction. B) Riemer-tiemann reaction. C) Swarts Reaction. D) Wurtz reaction. Show Answer Correct Answer: C) Swarts Reaction. 60. The types of mechanism in topic halolakane: A) No idea. B) S$_{N}$ 2. C) S$_{N}$ 1 & S$_{N}$ 2. D) S$_{N}$ 1$_{ }$. Show Answer Correct Answer: C) S$_{N}$ 1 & S$_{N}$ 2. ← 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 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 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