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 3 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Chemistry (Part Ii) Chapter 10 Haloalkanes And Haloarenes Quiz 3 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. What is the main use of chloroform (CHCl3)? A) Food preservative in packaging. B) Pesticide for agricultural use. C) Solvent and chemical production. D) Refrigerant in air conditioning systems. Show Answer Correct Answer: C) Solvent and chemical production. 2. Which haloalkane is most likely to undergo elimination reactions? A) Secondary haloalkane. B) Vinyl haloalkane. C) Primary haloalkane. D) Tertiary haloalkane. Show Answer Correct Answer: D) Tertiary haloalkane. 3. What is the IUPAC name for CH3CH2CH2CH2CH2Br? A) Pentyl bromide. B) Butyl bromide. C) Hexyl bromide. D) Methyl bromide. Show Answer Correct Answer: A) Pentyl bromide. 4. What are haloalkanes and how are they classified? A) Haloalkanes are organic compounds formed by replacing hydrogen in alkanes with halogens, classified as primary, secondary, or tertiary based on the carbon structure. B) Haloalkanes are classified only by their boiling points. C) Haloalkanes are inorganic compounds with no carbon structure. D) Haloalkanes are formed by adding hydrogen to alkenes. Show Answer Correct Answer: A) Haloalkanes are organic compounds formed by replacing hydrogen in alkanes with halogens, classified as primary, secondary, or tertiary based on the carbon structure. 5. Which of the following statements is not correct about S$_{N}$2 reaction of alkyl halides? A) The rate of reaction depends upon the concentration of nucleophile. B) The bond formation and bond breaking take place in one step. C) S$_{N}$2 mechanism is predominant in tertiary alkyl halides. D) Nucleophile attacks the carbon from the side opposite to where the leaving group is attached. Show Answer Correct Answer: C) S$_{N}$2 mechanism is predominant in tertiary alkyl halides. 6. Which alkyl halide exhibits complete racemization in S$_{N}$1 reaction? A) C$_{6}$H$_{5}$CH$_{2}$Cl. B) CH$_{3}$CH$_{2}$Cl. C) (CH$_{3}$)$_{2}$CHCl. D) CH$_{3}$CH$_{2}$CH$_{2}$Cl. Show Answer Correct Answer: A) C$_{6}$H$_{5}$CH$_{2}$Cl. 7. Mechanism of hydrolysis of 2-chloro-2-methylpropane to 2-methyl-2-propanol A) S$_{N}$1. B) S$_{N}$2. C) All the above. D) None of the above. Show Answer Correct Answer: A) S$_{N}$1. 8. Which of the following alkyl halide is most readily undergoes hydrolysis by SN$^{1}$ mechanism? A) CH$_{3}$CH$_{2}$CH$_{2}$Cl. B) CH$_{3}$Cl. C) (CH$_{3}$)$_{2}$ CHCl. D) (CH$_{3}$)$_{3}$ CCl. Show Answer Correct Answer: D) (CH$_{3}$)$_{3}$ CCl. 9. Halogen compounds have ..... boiling point than the parent hydrocarbons A) Unpredictable. B) Lower. C) Higher. D) Same. Show Answer Correct Answer: C) Higher. 10. What is the effect of halogenation on the reactivity of alkenes? A) Halogenation decreases the reactivity of alkenes. B) Halogenation only affects the physical properties of alkenes. C) Halogenation has no effect on the reactivity of alkenes. D) Halogenation increases the reactivity of alkenes by forming more stable intermediates. Show Answer Correct Answer: D) Halogenation increases the reactivity of alkenes by forming more stable intermediates. 11. Cyclobutyl bromide on treatment with Mg in dry ether forms an organometallic compound (A). the organometallic compound reacts with ethanal to give an alcohol(B) after mild acidification. Prolonged treatment of OH (B) with an equivalent amount of HBr gives (C). What will be the product 'C? A) 1-chloro-1-ethylcyclopentane. B) 1-bromo-1-methylcyclopentane. C) 3-bromo-2-methylcyclopentane. D) None of these. Show Answer Correct Answer: B) 1-bromo-1-methylcyclopentane. 12. What is the effect of the halogen atom on the boiling point of haloalkanes? A) The boiling point of haloalkanes is unaffected by the size of the halogen atom. B) The boiling point of haloalkanes decreases with the size of the halogen atom. C) The boiling point of haloalkanes increases with the size of the halogen atom. D) The boiling point of haloalkanes increases with the size of the carbon chain. Show Answer Correct Answer: C) The boiling point of haloalkanes increases with the size of the halogen atom. 13. A is a secondary haloalkane with formula C$_{5}$H$_{11}$Br and optically active. Identify A. A) CH$_{3}$CH$_{2}$CH$_{2}$CH$_{2}$CH$_{2}$Br. B) CH$_{3}$CH(Br)CH$_{2}$CH$_{2}$CH$_{3}$. C) (CH$_{3}$)$_{2}$C(Br)CH$_{2}$CH$_{3}$. D) (CH$_{3}$)$_{2}$C(Br)C(CH$_{3}$)$_{2}$CH$_{2}$CH$_{3}$. Show Answer Correct Answer: B) CH$_{3}$CH(Br)CH$_{2}$CH$_{2}$CH$_{3}$. 14. Assertion:The presence of multiple halogen atoms in haloalkanes increases their reactivity. Reason:More halogens lead to a greater electrophilic character of the carbon atom. A) The assertion is false, but the reason is true. B) Both the assertion and reason are false, and the reason does not explain the assertion. C) Both the assertion and reason are true, and the reason correctly explains the assertion. D) The assertion is true, but the reason is false. Show Answer Correct Answer: C) Both the assertion and reason are true, and the reason correctly explains the assertion. 15. What is the significance of the leaving group in haloalkane reactions? A) The leaving group only influences the product stability. B) The leaving group significantly impacts the reaction rate and mechanism in haloalkane reactions. C) The leaving group determines the color of the reaction mixture. D) The leaving group has no effect on the reaction rate. Show Answer Correct Answer: B) The leaving group significantly impacts the reaction rate and mechanism in haloalkane reactions. 16. What are some common applications of haloalkanes and haloarenes in industry? A) Common applications include solvents, chemical intermediates, pharmaceuticals, agrochemicals, refrigerants, and flame retardants. B) Textile dyes. C) Construction materials. D) Food preservatives. Show Answer Correct Answer: A) Common applications include solvents, chemical intermediates, pharmaceuticals, agrochemicals, refrigerants, and flame retardants. 17. Complete the following reaction R-OH + X $\rightarrow$ A) SOCl3. B) SOCl2. C) SOCl. D) SO2. Show Answer Correct Answer: B) SOCl2. 18. Which reagent is commonly used to convert arenes to haloarenes? A) Chlorine (Cl2) with no catalyst. B) Bromine (Br2) with a catalyst. C) Iodine (I2) in aqueous solution. D) Sulfuric acid (H2SO4) alone. Show Answer Correct Answer: B) Bromine (Br2) with a catalyst. 19. Which type of reaction leads to a mixture of enantiomers? A) Neither. B) S N 2 reactions. C) Both. D) S N 1 reactions. Show Answer Correct Answer: D) S N 1 reactions. 20. What is the primary environmental impact of using halogenated solvents? A) They are responsible for water contamination. B) They have no significant environmental impact. C) They contribute to soil erosion. D) They can lead to air pollution. Show Answer Correct Answer: A) They are responsible for water contamination. 21. What is the general reaction for the preparation of aryl halides? A) Nucleophilic aromatic substitution. B) Free radical substitution. C) Electrophilic aromatic substitution. D) Electrophilic aliphatic substitution. Show Answer Correct Answer: C) Electrophilic aromatic substitution. 22. What is the classification of haloalkanes based on the number of halogen atoms? A) Saturated and unsaturated. B) Mono, di, and tri. C) Primary, secondary, and tertiary. D) Alkyl, allylic, and aryl. Show Answer Correct Answer: B) Mono, di, and tri. 23. The order of reactivity of following alcohols with halogen acids is ..... (A) Propan-1-ol (B) Butane-2-ol (C) 2-Methyl butan-2-ol A) B B) A C) C D) A Show Answer Correct Answer: B) A 24. Why tertiary alcohols are prone to Sn1 mechanism? A) Tertiary alcohols is more stable. B) Due to low stability of tertiary carbocation. C) Due to high stability of tertiary carbocation. D) Tertiary alcohols is less stable. Show Answer Correct Answer: C) Due to high stability of tertiary carbocation. 25. Assertion:Electron withdrawing groups in aryl halides increases the reactivity towards nucleophilic substitution.Reason:2, 4-Dinitrochlorobenzene is more reactive than chlorobenzene. A) Both assertion and reason are true and the reason is the correct explanation of the assertion. B) Both assertion and reason are true but reason is not the correct explanation of the assertion. C) Assertion is true but reason is false. D) Assertion is false but reason is true. Show Answer Correct Answer: B) Both assertion and reason are true but reason is not the correct explanation of the assertion. 26. Haloarenes are typically less reactive than haloalkanes due to: A) Molecular weight. B) Resonance stabilization. C) Electronegativity. D) Steric hindrance. Show Answer Correct Answer: B) Resonance stabilization. 27. Which among MeX, RCH$_{2}$X, R$_{2}$CHX and R$_{3}$CX is most reactive towards SN$^{2}$ reaction A) MeX. B) R$_{3}$CX. C) RCH$_{2}$X. D) R$_{2}$CHX. Show Answer Correct Answer: A) MeX. 28. What is the primary mechanism by which haloalkanes react with nucleophiles? A) Nucleophilic substitution. B) Electrophilic addition. C) Free radical substitution. D) Electrophilic substitution. Show Answer Correct Answer: A) Nucleophilic substitution. 29. In carbylamine reaction the main product is A) Isocyanide. B) Cyanide. C) Alcohol. D) None of the above. Show Answer Correct Answer: A) Isocyanide. 30. Alkaline hydrolysis of (CH$_{3}$)$_{3}$CBr involves two steps as follows.(CH$_{3}$)$_{3}$CBr $\rightarrow$ (CH$_{3}$)$_{3}$C$^{+}$ + Br$^{-}$ slow(CH$_{3}$)$_{3}$C$^{+ }$+ OH-$\rightarrow$ (CH$_{3}$)$_{3}$COH fastWhich of the following shows the rate equation for the reaction scheme? A) Rate = k[(CH$_{3}$)$_{3}$CBr]$^{2}$. B) Rate = k[OH$^{-}$]. C) Rate = k[(CH$_{3}$)$_{3}$CBr][OH$^{-}$]. D) Rate = k[(CH$_{3}$)$_{3}$CBr]. Show Answer Correct Answer: D) Rate = k[(CH$_{3}$)$_{3}$CBr]. 31. List two physical properties of haloalkanes that differ from alkanes. A) Higher boiling points and greater density. B) Similar boiling points and lower reactivity. C) Higher melting points and lower solubility. D) Lower boiling points and lower density. Show Answer Correct Answer: A) Higher boiling points and greater density. 32. Common name for methylbenzene ..... A) Toluene. B) Alkyl halides. C) All the above. D) None of the above. Show Answer Correct Answer: A) Toluene. 33. Explain the mechanism of nucleophilic substitution in haloalkanes. A) Haloalkanes cannot undergo nucleophilic substitution reactions. B) SN1 and SN2 mechanisms are exclusive to alcohols. C) Nucleophilic substitution in haloalkanes can occur via SN1 or SN2 mechanisms. D) Nucleophilic substitution only occurs in aromatic compounds. Show Answer Correct Answer: C) Nucleophilic substitution in haloalkanes can occur via SN1 or SN2 mechanisms. 34. How do you differentiate between ortho, meta, and para substitutions in haloarenes? A) Ortho:1, 4; Meta:1, 2; Para:1, 3 positions. B) Ortho:1, 3; Meta:1, 2; Para:1, 5 positions. C) Ortho:1, 2; Meta:1, 3; Para:1, 4 positions. D) Ortho:1, 1; Meta:1, 2; Para:1, 3 positions. Show Answer Correct Answer: C) Ortho:1, 2; Meta:1, 3; Para:1, 4 positions. 35. Which is the correct increasing order of boiling points of the following compounds? 1-Iodobutane, 1-Bromobutane, 1-Chlorobutane, Butane A) 1-Iodobutane < 1-Bromobutane < 1-Chlorobutane < Butane. B) Butane < 1-Iodobutane < 1-Bromobutane < 1-Chlorobutane. C) Butane < 1-Chlorobutane < 1-Bromobutane < 1-Iodobutane. D) Butane < 1-Chlorobutane < 1-Iodobutane < 1-Bromobutane. Show Answer Correct Answer: C) Butane < 1-Chlorobutane < 1-Bromobutane < 1-Iodobutane. 36. Which hormone produced by the body contains iodine? A) Cortisol. B) Insulin. C) Adrenaline. D) Thyroxine. Show Answer Correct Answer: D) Thyroxine. 37. What type of substrates are involved in S N 2 reactions? A) Quaternary carbon atom. B) Primary carbon atom. C) Aromatic carbon atom. D) Tertiary or secondary carbon atom. Show Answer Correct Answer: B) Primary carbon atom. 38. Reaction of trans-2-phenyl-1-bromocyclopentane on reaction with alcoholic KOH produces A) 3-phenylcyclopentene. B) 4-phenylcyclopentene. C) 1-phenylcyclopentene. D) 2-phenylcyclopentene. Show Answer Correct Answer: A) 3-phenylcyclopentene. 39. What can Grignard reagents be used as in the synthesis of complex molecules in the pharmaceutical and chemical industry? A) Inhibitors. B) Catalysts. C) Building blocks. D) Solvents. Show Answer Correct Answer: C) Building blocks. 40. What is the main product when chlorobenzene undergoes nucleophilic substitution with sodium hydroxide at high temperature? A) Chlorobenzene oxide. B) Aniline. C) Phenol. D) Benzene. Show Answer Correct Answer: C) Phenol. 41. What is the significance of the C-X bond in haloalkanes? A) The C-X bond is only important for color changes in haloalkanes. B) The C-X bond is irrelevant in determining the boiling point of haloalkanes. C) The C-X bond in haloalkanes is significant for determining reactivity and properties due to its polarity and bond strength. D) The C-X bond has no effect on the solubility of haloalkanes in water. Show Answer Correct Answer: C) The C-X bond in haloalkanes is significant for determining reactivity and properties due to its polarity and bond strength. 42. What is the main product when a haloalkane reacts with a strong base? A) Alkene. B) Alkane. C) Alcohol. D) Carboxylic acid. Show Answer Correct Answer: A) Alkene. 43. Which of the following haloalkanes is most reactive? A) 2-chloropropane. B) 1-bromopropane. C) 2-bromopropane. D) 1-chloropropane. Show Answer Correct Answer: C) 2-bromopropane. 44. What is the IUPAC name for CH3CH2Cl? A) Chloroethanol. B) 1-chloroethane. C) Ethyl chloride. D) 1-chloropropane. Show Answer Correct Answer: B) 1-chloroethane. 45. What is the primary reaction type for haloalkanes with strong nucleophiles? A) SN2 reaction. B) E1 reaction. C) SN1 reaction. D) Elimination reaction. Show Answer Correct Answer: A) SN2 reaction. 46. SN1 reaction of alkyl halides lead to A) Retention of configuration. B) Racemisation. C) Inversion of configuration. D) None of these. Show Answer Correct Answer: A) Retention of configuration. 47. Assertion:Halogen acids react with alcohols to form haloalkanes.Reason:Order of reactivity of halogen acids HCl>HBr>HI A) Both assertion and reason are true and the reason is the correct explanation of the assertion. B) Both assertion and reason are true but reason is not the correct explanation of the assertion. C) Assertion is true but reason is false. D) Assertion is false but reason is true. Show Answer Correct Answer: C) Assertion is true but reason is false. 48. Chloroform react with oxygen to form A) Phosgene. B) COCl2. C) Poisonous gas that can damage liver and kidney. D) All of these. Show Answer Correct Answer: D) All of these. 49. Ethyl alcohol is obtained when ethyl chloride is boiled with A) Alcoholic KOH. B) Aqueous KOH. C) Water. D) Aqueous KMnO4. Show Answer Correct Answer: B) Aqueous KOH. 50. What is the mechanism of nucleophilic substitution in haloalkanes? A) Nucleophilic substitution in haloalkanes occurs via SN1 and SN2 mechanisms. B) Nucleophilic substitution is exclusively an acid-base reaction. C) Haloalkanes undergo substitution via radical mechanisms. D) Nucleophilic substitution occurs only through the elimination mechanism. Show Answer Correct Answer: A) Nucleophilic substitution in haloalkanes occurs via SN1 and SN2 mechanisms. 51. Which type of solvent is preferred for S N 1 reactions? A) Polar protic solvents. B) Non-polar solvents. C) Ionic solvents. D) Polar aprotic solvents. Show Answer Correct Answer: A) Polar protic solvents. 52. S$_{N}$2 is a ..... step mechanism A) One. B) Two. C) All the above. D) None of the above. Show Answer Correct Answer: A) One. 53. Reactivity towards Nu-subs.:haloarenes vs haloalkanes A) Delocalisation reduce partial +ve charge on halogen-carrying C atom making it less susceptible to attack by Nu-. B) Delocalisation increase partial +ve charge on halogen-carrying C atom making it less susceptible to attack by Nu-. C) All the above. D) None of the above. Show Answer Correct Answer: A) Delocalisation reduce partial +ve charge on halogen-carrying C atom making it less susceptible to attack by Nu-. 54. Complete the following reaction R-X + KNO2 $\rightarrow$ A + KXA is A) RNO. B) RNO3. C) RONO. D) RNO2. Show Answer Correct Answer: C) RONO. 55. Name the two main types of nucleophilic substitution reactions. A) SNi and SNe. B) SN1 and SNi. C) SN3 and SN4. D) SN1 and SN2. Show Answer Correct Answer: D) SN1 and SN2. 56. Most strong C-X bond (important for rate substitution). betweenC-FC-ClC-BrC-I A) C-Br. B) C-I. C) C-Cl. D) C-F. Show Answer Correct Answer: D) C-F. 57. What is nucleophilic substitution? A) A reaction where two nucleophiles combine to form a larger molecule. B) A reaction that only occurs in the presence of a catalyst. C) A chemical reaction where a nucleophile replaces a leaving group in a molecule. D) A process that involves the addition of a leaving group to a nucleophile. Show Answer Correct Answer: C) A chemical reaction where a nucleophile replaces a leaving group in a molecule. 58. 2-Chloro-2-methylpropane on reaction with alc.KOH gives X as the product. X is A) But-2-ene. B) 2-methylbut-1-ene. C) 2-methyobutan-2-ol. D) 2-methylprop-1-ene. Show Answer Correct Answer: D) 2-methylprop-1-ene. 59. How do you determine the stability of carbocations formed during nucleophilic substitution? A) The stability is solely based on the molecular weight of the carbocation. B) Carbocation stability is determined by the temperature of the reaction. C) The presence of halogens increases carbocation stability. D) The stability of carbocations is determined by hybridization, substituent effects, resonance, and steric factors. Show Answer Correct Answer: D) The stability of carbocations is determined by hybridization, substituent effects, resonance, and steric factors. 60. Name a common reaction that haloarenes undergo instead of nucleophilic substitution. A) Dehydrohalogenation. B) Nucleophilic addition. C) Electrophilic aromatic substitution. D) Radical substitution. Show Answer Correct Answer: C) Electrophilic aromatic substitution. ← 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 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