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 1 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 1 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Why chloroform is stored in closed dark coloured bottles?? A) Chloroform is very poisonous. B) Chloroform is a very reactive gas. C) Chloroform causes damage to CNS, liver, kidneys. D) Chloroform is oxidised by air to phosgene. Show Answer Correct Answer: D) Chloroform is oxidised by air to phosgene. 2. Ambident nucleophile is A) Cl. B) CN. C) H2O. D) NH2. Show Answer Correct Answer: B) CN. 3. What is a common application of haloalkanes in the pharmaceutical industry? A) Synthesis of pharmaceuticals. B) Solvent for chemical reactions. C) Preservative in food products. D) Fuel for combustion engines. Show Answer Correct Answer: A) Synthesis of pharmaceuticals. 4. Classify the following compounds as primary, secondary and tertiary halides.i) 1-Bromobut-2-eneii) 4-Bromopent-2-eneiii) 2-Bromo-2-methylpropane A) (i) secondary, (ii) tertiary, (iii) primary. B) (i)primary, (ii) secondary, (iii) tertiary. C) (i)primary, (ii) tertiary, (iii) secondary. D) (i) secondary, (ii) primary, (iii) tertiary. Show Answer Correct Answer: B) (i)primary, (ii) secondary, (iii) tertiary. 5. What is the effect of increasing the number of halogen substituents on the stability of haloalkanes? A) Stability increases with more halogen substituents. B) Stability remains unchanged regardless of halogen number. C) Stability decreases with more halogen substituents. D) Stability is only affected by the type of halogen present. Show Answer Correct Answer: C) Stability decreases with more halogen substituents. 6. What is the effect of temperature on nucleophilic substitution reactions? A) Higher temperatures decrease reaction rates. B) Increasing temperature generally increases the rate of nucleophilic substitution reactions, but very high temperatures may lead to side reactions. C) Increasing temperature always leads to more favorable products. D) Temperature has no effect on nucleophilic substitution reactions. Show Answer Correct Answer: B) Increasing temperature generally increases the rate of nucleophilic substitution reactions, but very high temperatures may lead to side reactions. 7. Which of the reaction follows Markonikovs rule A) C$_{2}$H$_{4}$ + HBr. B) C$_{3}$H$_{6}$ + Br$_{2}$. C) C$_{3}$H$_{6}$ + HBr. D) C$_{3}$H$_{6}$ + Cl$_{2}$. Show Answer Correct Answer: C) C$_{3}$H$_{6}$ + HBr. 8. The negative part of the addendum ( the molecule to be added) adds on to the carbon atom of the double bond containing the least number of hydrogen atoms. This rule is known as A) Hoffmann rule. B) Saytzeff's rule. C) Peroxide rule. D) Markovnikov's rule. Show Answer Correct Answer: D) Markovnikov's rule. 9. What is Lucas Reagent? A) Conc HCl + And. FeCl3. B) Conc HCl + And. ZnCl2. C) Conc HCl + And. AlCl3. D) Conc HBr + And. FeCl3. Show Answer Correct Answer: B) Conc HCl + And. ZnCl2. 10. Alkyl halides are immiscible in water though they are polar because A) They are stable compounds are not reactive. B) C-X bond cannot be broken easily. C) They cannot form hydrogen bonds with water. D) They react with water to give alcohols. Show Answer Correct Answer: C) They cannot form hydrogen bonds with water. 11. What is the role of a catalyst in the preparation of haloarenes? A) The catalyst is used to remove impurities from haloarenes. B) A catalyst is necessary for the formation of haloarenes without any reaction. C) A catalyst decreases the reaction rate of haloarenes. D) The role of a catalyst is to increase the reaction rate and yield of haloarenes by facilitating electrophilic substitution. Show Answer Correct Answer: D) The role of a catalyst is to increase the reaction rate and yield of haloarenes by facilitating electrophilic substitution. 12. Fitting reaction can be used to prepare A) Acetophenon. B) Diphenyl. C) Chlorobenzene. D) Toluene. Show Answer Correct Answer: D) Toluene. 13. Chloroethane, chlorobenzene, (chloromethyl)benzene All three organic substances above can react with A) Bromine water at room temperature. B) Acidified potassium dichromate under reflux. C) Aqueous solution of sodium hydroxide at room temperature. D) Magnesium in dry ether. Show Answer Correct Answer: D) Magnesium in dry ether. 14. What is the stereochemical outcome of an SN2 reaction? A) Retention of configuration at the chiral center. B) No change in stereochemistry. C) Formation of a racemic mixture. D) Inversion of configuration at the chiral center. Show Answer Correct Answer: D) Inversion of configuration at the chiral center. 15. Which of the following species is/are nucleophile(s)? I. OH$^{-}$ II. H$_{2}$OIII. R$_{3}$C$^{-}$ 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. 16. Chlorobenzene is formed by reaction of chlorine with benzene in the presence of AlCl$_{3}$ . Whichof the following species attacks the benzene ring in this reaction? A) [AlCl$_{4}$ ]$^{-}$. B) Cl$^{+}$. C) AlCl$_{3}$. D) Cl$^{-}$. Show Answer Correct Answer: B) Cl$^{+}$. 17. Which halogen atom size increases the most in haloalkanes? A) Chlorine. B) Fluorine. C) Iodine. D) Bromine. Show Answer Correct Answer: C) Iodine. 18. Which of the following compounds will have highest melting point? A) O-dichlorobenzene. B) Chlorobenzene. C) M-dicholorbenzene. D) P-dichlorobenzene. Show Answer Correct Answer: D) P-dichlorobenzene. 19. What are the common methods for preparing haloarenes? A) Hydrogenation of haloarenes. B) Common methods for preparing haloarenes include halogenation of arenes, nucleophilic substitution, electrophilic aromatic substitution, Sandmeyer reaction, and Finkelstein reaction. C) Oxidation of haloarenes. D) Dehydrohalogenation of haloalkanes. Show Answer Correct Answer: B) Common methods for preparing haloarenes include halogenation of arenes, nucleophilic substitution, electrophilic aromatic substitution, Sandmeyer reaction, and Finkelstein reaction. 20. How do you prepare haloalkanes from alcohols? A) Haloalkanes are formed by heating alcohols with water. B) Haloalkanes can be synthesized by oxidizing alcohols with oxygen. C) Haloalkanes are prepared from alcohols by reacting them with hydrogen halides or phosphorus halides. D) Haloalkanes are produced by mixing alcohols with sodium chloride. Show Answer Correct Answer: C) Haloalkanes are prepared from alcohols by reacting them with hydrogen halides or phosphorus halides. 21. What is the main difference between haloalkanes and haloarenes? A) Haloalkanes have halogens attached to saturated carbons, while haloarenes have halogens attached to aromatic rings. B) Haloalkanes are always liquid, while haloarenes are always solid. C) Haloalkanes are more reactive than haloarenes due to their structure. D) Haloalkanes contain only carbon and hydrogen, while haloarenes contain oxygen. Show Answer Correct Answer: A) Haloalkanes have halogens attached to saturated carbons, while haloarenes have halogens attached to aromatic rings. 22. Tertiary butyl bromide on reaction with Na methoxide mainly gives A) Propene. B) Tert-butyl ethyl ether. C) Iso-propyl alcohol. D) 2-methylpropene. Show Answer Correct Answer: D) 2-methylpropene. 23. How do polar protic solvents affect SN1 and SN2 reactions? A) Polar protic solvents favor SN1 reactions and hinder SN2 reactions. B) Polar protic solvents have no effect on SN1 or SN2 reactions. C) Polar protic solvents only affect the rate of SN2 reactions. D) Polar protic solvents favor SN2 reactions and hinder SN1 reactions. Show Answer Correct Answer: A) Polar protic solvents favor SN1 reactions and hinder SN2 reactions. 24. Which type of nucleophilic substitution is favored by tertiary haloalkanes? A) SN1. B) E2. C) E1. D) SN2. Show Answer Correct Answer: A) SN1. 25. How can haloalkanes be synthesized from alcohols? A) By oxidizing alcohols with potassium permanganate. B) By polymerizing alcohols with ethylene. C) Haloalkanes can be synthesized from alcohols by reacting them with hydrogen halides or using reagents like SOCl2 or PBr3. D) By heating alcohols with sodium chloride. Show Answer Correct Answer: C) Haloalkanes can be synthesized from alcohols by reacting them with hydrogen halides or using reagents like SOCl2 or PBr3. 26. Name the following haloalkane:CH3CH2CH2I A) 3-iodopropane. B) 2-iodopropane. C) 1-iodopropane. D) 1-iodobutane. Show Answer Correct Answer: C) 1-iodopropane. 27. The synthesis of alkyl fluoride is best accomplished by:(JEE 2015 C) A) Finkelstein reaction. B) Swarts reaction. C) Free radical fluorination. D) Sandmeyer's reaction. Show Answer Correct Answer: B) Swarts reaction. 28. What is the rate-determining step in an SN1 reaction? A) The formation of the carbocation intermediate. B) The leaving group departing from the substrate. C) The formation of a transition state. D) The nucleophile attacking the substrate. Show Answer Correct Answer: A) The formation of the carbocation intermediate. 29. Give the reaction conditions for dow's processes A) NaOH, 368K, 300atm in Basic medium. B) NaOH, 623K, 300atm in acidic medium. C) NaOH, 443K, 300atm in acidic medium. D) NaOH, 623K, 300atm in Basic medium. Show Answer Correct Answer: B) NaOH, 623K, 300atm in acidic medium. 30. What is the role of a leaving group in nucleophilic substitution reactions? A) Leaving groups only affect the final product of the reaction. B) A good leaving group facilitates the reaction by stabilizing the transition state. C) The leaving group has no impact on the reaction mechanism. D) The leaving group must be a strong nucleophile. Show Answer Correct Answer: B) A good leaving group facilitates the reaction by stabilizing the transition state. 31. Assertion:The Friedel-Crafts alkylation is a method to prepare haloarenes. Reason:This reaction involves the introduction of an alkyl group into the aromatic ring. A) True, False. B) False, True. C) True, True. D) False, False. Show Answer Correct Answer: B) False, True. 32. Give the reaction conditions when chlorobenze react to sodium hydroxide to give nucleophilic substitution reaction. A) NaOH, 368K, 300atm in Basic medium. B) NaOH, 623K, 300atm in acidic medium. C) NaOH, 623K, 300atm in Basic medium. D) NaOH, 443K, 300atm in acidic medium. Show Answer Correct Answer: B) NaOH, 623K, 300atm in acidic medium. 33. What is the effect of branching on the boiling point of haloalkanes? A) Branching increases the boiling point of haloalkanes. B) Branching lowers the boiling point of haloalkanes. C) Branching makes haloalkanes boil at a constant temperature. D) Branching has no effect on the boiling point of haloalkanes. Show Answer Correct Answer: B) Branching lowers the boiling point of haloalkanes. 34. When chlorobenzene is treated with Na in dry ether, the product formed is: A) Toluene. B) Biphenyl. C) Benzyl chloride. D) Benzene. Show Answer Correct Answer: B) Biphenyl. 35. Methyl ketone is identified by A) Haloform test. B) Iodoform test. C) Tollens reagent. D) None of the above. Show Answer Correct Answer: B) Iodoform test. 36. In the Wurtz reaction, the product obtained from two different alkyl halides is: A) A single alkane. B) An alcohol. C) A mixture of three alkanes. D) An alkene. Show Answer Correct Answer: C) A mixture of three alkanes. 37. Which of the following is a method for the preparation of aryl halides? A) Free radical halogenation. B) Hydrolysis. C) Electrophilic substitution. D) Dehydrohalogenation. Show Answer Correct Answer: C) Electrophilic substitution. 38. What is the role of haloalkanes in organic synthesis? A) Haloalkanes are only used in the production of pharmaceuticals. B) Haloalkanes are primarily used as solvents in organic reactions. C) Haloalkanes serve as catalysts in polymerization processes. D) Haloalkanes are key intermediates in organic synthesis, facilitating the formation of various functional groups through nucleophilic substitution and elimination reactions. Show Answer Correct Answer: D) Haloalkanes are key intermediates in organic synthesis, facilitating the formation of various functional groups through nucleophilic substitution and elimination reactions. 39. Which haloalkane is most soluble in water? A) Ethyl bromide (C2H5Br). B) Methyl chloride (CH3Cl). C) Isopropyl chloride (C3H7Cl). D) Benzyl chloride (C6H5CH2Cl). Show Answer Correct Answer: B) Methyl chloride (CH3Cl). 40. Ethyl bromide on treatment with silver cyanide give: A) Ethyl amine. B) Ethyl iso cyanide. C) Ethyl cyanide. D) Ethyl acetate. Show Answer Correct Answer: B) Ethyl iso cyanide. 41. How do you name a haloalkane with multiple halogen substituents? A) Name the compound based on the highest atomic number halogen only. B) Use Roman numerals for each halogen. C) List halogens in reverse alphabetical order. D) Use the IUPAC naming convention, listing halogens in alphabetical order with appropriate locants. Show Answer Correct Answer: D) Use the IUPAC naming convention, listing halogens in alphabetical order with appropriate locants. 42. How do haloarenes differ from haloalkanes in terms of reactivity? A) Haloarenes react only with nucleophiles. B) Haloarenes are less reactive than haloalkanes. C) Haloalkanes are less stable than haloarenes. D) Haloarenes are more reactive than haloalkanes. Show Answer Correct Answer: B) Haloarenes are less reactive than haloalkanes. 43. The most reactive halogen in halogenations of alkanes under sunlight A) I. B) F. C) Br. D) Cl. Show Answer Correct Answer: D) Cl. 44. WHICH OF THEC FOLLOWING IS USED AS AN ANTISEPTIC? A) IODOFORM. B) CHLOFORM. C) BROMFORM. D) CARBON TETRA CHLORIDE. Show Answer Correct Answer: A) IODOFORM. 45. The compounds used as refrigerant are A) CCl4. B) CH2F2. C) CF4. D) CF2Cl2. E) NH3. Show Answer Correct Answer: D) CF2Cl2. 46. What is the reaction mechanism involved in the preparation of alkyl halides from alcohols? A) Substitution reaction. B) Oxidation reaction. C) Elimination reaction. D) Addition reaction. Show Answer Correct Answer: A) Substitution reaction. 47. Why does the reaction C$_{2}$H$_{5}$X + OH$^{-}$ $\rightarrow$ C$_{2}$H$_{5}$OH + X$^{-}$ occur faster if X is iodine instead of Bromine? A) The C-Br bond is stronger than the C-I bond. B) The I$^{-}$ ion is less hydrated in water than the Br$^{-}$ ion. C) The I$^{-}$ion is a stronger nucleophile than the Br$^{-}$ion. D) C-Br bond is more polar than the C-I bond. Show Answer Correct Answer: A) The C-Br bond is stronger than the C-I bond. 48. S$_{N}$1 stand for A) Unimolecular nucleophilic substitution. B) Bimolecular nucleophilic substitution. C) All the above. D) None of the above. Show Answer Correct Answer: A) Unimolecular nucleophilic substitution. 49. Halogenation, Sulphonation, Friedel-Crafts reactionof haloarene comes under A) Addition reaction. B) Electrophilic substitution reaction. C) Nucleophilic substitution reaction. D) Elimination reaction. Show Answer Correct Answer: B) Electrophilic substitution reaction. 50. Provide an example of an electrophilic substitution reaction involving an aryl halide. A) Bromobenzene + HNO3/H2SO4 $\rightarrow$ Nitrobenzene + HBr. B) Chlorobenzene + H2SO4 $\rightarrow$ Phenol + HCl. C) Fluorobenzene + Br2/FeBr3 $\rightarrow$ Bromobenzene + HF. D) Iodobenzene + H2O2/H+ $\rightarrow$ Hydroxybenzene + HI. Show Answer Correct Answer: A) Bromobenzene + HNO3/H2SO4 $\rightarrow$ Nitrobenzene + HBr. 51. What is the main environmental concern regarding haloalkanes? A) Ozone layer depletion and environmental toxicity. B) Increased carbon emissions from vehicles. C) Destruction of marine habitats by plastics. D) Overpopulation of urban areas due to industrialization. Show Answer Correct Answer: A) Ozone layer depletion and environmental toxicity. 52. What is the impact of electron-withdrawing groups on the reactivity of haloalkanes? A) Electron-withdrawing groups only affect the boiling point of haloalkanes. B) Electron-withdrawing groups increase the reactivity of haloalkanes. C) Electron-withdrawing groups have no effect on the reactivity of haloalkanes. D) Electron-withdrawing groups decrease the reactivity of haloalkanes. Show Answer Correct Answer: D) Electron-withdrawing groups decrease the reactivity of haloalkanes. 53. Assertion (A):Nitration of chlorobenzene leads to the formation of ortho and para nitrochlorobenzene.Reason (R):-NO$_{2}$ group is o and p-directing group. 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 A. C) A is correct; R is incorrect. D) A is incorrect; R is correct. Show Answer Correct Answer: C) A is correct; R is incorrect. 54. Molecules whose mirror image is non-superimposable over them are known as chiral. Which of the following molecules is chiral in nature? A) 2-bromopropane. B) 1-bromobutane. C) 2-bromobutane. D) 2-bromopropan-2-ol. Show Answer Correct Answer: C) 2-bromobutane. 55. How do haloalkanes undergo elimination reactions? A) Haloalkanes decompose directly into alkynes. B) Haloalkanes react with water to form alcohols. C) Haloalkanes undergo elimination reactions via E1 or E2 mechanisms, leading to the formation of alkenes. D) Haloalkanes can only undergo substitution reactions. Show Answer Correct Answer: C) Haloalkanes undergo elimination reactions via E1 or E2 mechanisms, leading to the formation of alkenes. 56. Which type of nucleophiles are involved in S N 2 reactions? A) Electrophiles. B) Strong nucleophiles. C) Neutral nucleophiles. D) Weak nucleophiles. Show Answer Correct Answer: B) Strong nucleophiles. 57. Methyl bromide reacts with AgF to give methyl fluoride and silver bromide. This reaction is called A) Swarts reaction. B) Wurtz reaction. C) Fiitig reaction. D) Finkelstein reaction. Show Answer Correct Answer: A) Swarts reaction. 58. Describe the electrophilic aromatic substitution mechanism using bromobenzene as an example. A) Direct substitution without a sigma complex. B) Formation of a carbocation intermediate. C) The electrophilic aromatic substitution mechanism involves the formation of a bromonium ion, attack by the aromatic ring, formation of a sigma complex, and loss of a proton to restore aromaticity. D) Loss of a bromine atom instead of a proton. Show Answer Correct Answer: C) The electrophilic aromatic substitution mechanism involves the formation of a bromonium ion, attack by the aromatic ring, formation of a sigma complex, and loss of a proton to restore aromaticity. 59. The reagent used to convert propene to propanol is A) I) HBr/Peroxide ii) KOH (alc.). B) I) HBr ii) KOH (alc.). C) I) HBr ii) KOH (aq.). D) I) HBr/Peroxide ii) KOH (aq.). Show Answer Correct Answer: D) I) HBr/Peroxide ii) KOH (aq.). 60. How does the strength of the nucleophile influence SN2 reactions? A) Weaker nucleophiles are preferred in SN2 reactions. B) The strength of the nucleophile has no effect on SN2 reactions. C) A stronger nucleophile increases the rate of SN2 reactions. D) Only neutral nucleophiles can participate in SN2 reactions. Show Answer Correct Answer: C) A stronger nucleophile increases the rate of SN2 reactions. Next →Related QuizzesScience QuizzesClass 12 QuizzesClass 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 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