97 Aromatic Compounds Quiz Batch 07Aromatic compounds are organic molecules containing conjugated pi-electron systems, typically following Huckel's rule (4n+2 π electrons). These compounds, such as benzene, exhibit resonance stability and unique chemical properties. Widely used in pharmaceuticals, dyes, and petrochemicals, aromatic compounds play a crucial role in organic chemistry. 1 / 32Ozonolysis of benzene gives Glycol Formaldehyde Acetaldehyde Glyoxal 2 / 32The formation of the nitronium ion (NO₂⁺) in nitration of benzene involves: A) Protonation of NO₂ B) Loss of water from protonated nitric acid C) Reaction of nitric acid with FeCl₃ D) Direct attack of NO₂⁺ on benzene 3 / 32Reaction of Isopropyl Benzene with Alkaline KMnO4 gives Ethyl Benzene Cumene n-propyl benzene None 4 / 32What is the product of the reaction between an arenediazonium salt and H₃PO₂? a) Benzene b) Phenol c) Aniline d) Nitrobenzene 5 / 32Why does benzene undergo electrophilic substitution rather than addition reactions? A) To maintain its aromatic stability B) Due to steric hindrance C) Because of strong C-H bonds D) None of the above 6 / 32Which of the following is true about the Gatterman-Koch reaction? a) It produces benzaldehyde b) It requires a stable acyl chloride c) It is a nucleophilic substitution reaction d) It does not require a catalyst 7 / 32Reaction of 2,4-dinitrobromobenzene with sodium cyanide gives 2-nitrobenzene 2,4-dinitrobenzene 2,4-dinitrobenzonitrile None 8 / 32Which is NOT a step in the electrophilic aromatic substitution mechanism? A) Formation of an arenium ion B) Addition of a nucleophile C) Loss of a proton D) Regeneration of aromaticity 9 / 32What is the product of the reaction between an arenediazonium salt and water? a) Phenol b) Benzene c) Aniline d) Nitrobenzene 10 / 32Why is an acyl group more stable on a benzene ring than an alkyl group in Friedel–Crafts reactions? A) Acyl groups do not activate the ring for further substitution B) Acyl groups form resonance-stabilized structures C) Acyl groups do not rearrange like alkyl groups D) All of the above 11 / 32In nucleophilic aromatic substitution (SNAr), the leaving group is more easily displaced when: A) A strong electron-donating group is present at the ortho position B) A strong electron-withdrawing group is present at the ortho or para position C) The benzene ring contains multiple alkyl substituents D) A weak base is used as a nucleophile 12 / 32Which of the following reagents can convert a nitrobenzene to an aniline? A) H₂/Pd B) Fe/HCl C) SnCl₂/HCl D) All of the above 13 / 32Why does aniline not undergo Friedel–Crafts reactions? A) The NH₂ group deactivates the ring B) The NH₂ group forms a complex with AlCl₃ C) Aniline is too basic D) AlCl₃ promotes oxidation of aniline 14 / 32What is the product of the Wolff-Kishner reduction of acetophenone? a) Ethylbenzene b) Toluene c) Benzene d) Phenol 15 / 32Cyclopentadienyl cation is Aromatic Anti-aromatic Non-aromatic None 16 / 32Why is primary carbocation formation avoided in Friedel–Crafts alkylation? A) Primary carbocations are too stable B) Primary carbocations undergo rearrangement C) Alkyl halides cannot ionize in the presence of AlCl₃ D) The reaction is too slow with primary carbocations 17 / 32What is the role of sulfuric acid in the nitration of benzene? A) Oxidizing agent B) Protonates nitric acid to generate NO₂⁺ C) Acts as a nucleophile D) None of the above 18 / 32Why is primary carbocation formation avoided in Friedel–Crafts alkylation? A) Primary carbocations are too stable B) Primary carbocations undergo rearrangement C) Alkyl halides cannot ionize in the presence of AlCl₃ D) The reaction is too slow with primary carbocations 19 / 32What is the major product of the Friedel-Crafts acylation of benzene with acetyl chloride? a) Acetophenone b) Benzaldehyde c) Toluene d) Benzoic acid 20 / 32Which of the following best explains why halogens are deactivating but ortho/para-directing in electrophilic aromatic substitution? A) Halogens withdraw electrons inductively but donate electrons by resonance B) Halogens are bulky and sterically hinder reactions C) Halogens act as bases in acidic media D) Halogens do not participate in resonance 21 / 32Which of the following is the most activating substituent for electrophilic aromatic substitution? A) -OH B) -NO₂ C) -Cl D) -CF₃ 22 / 32How can a straight-chain alkyl group be added to benzene without undergoing rearrangement? A) Friedel–Crafts alkylation B) Friedel–Crafts acylation followed by Wolff-Kishner reduction C) Direct alkylation with Grignard reagents D) Birch reduction 23 / 32Why does benzene not react with Br₂ under normal conditions like alkenes? A) Benzene lacks π-bonds B) Benzene has delocalized π-electrons, making it less reactive C) The reaction is too slow to be observed D) Br₂ is not a suitable electrophile for benzene 24 / 32Which of the following criteria is NOT necessary for a compound to be aromatic? A) Planarity B) Full conjugation of π-electrons C) Presence of an even number of π-electrons D) Obedience to Hückel’s rule 25 / 32Which of the following is true about the Sandmeyer reaction? a) It is used to introduce halogens onto the benzene ring b) It is a nucleophilic substitution reaction c) It requires a diazonium salt d) All of the above 26 / 32Which of the following properties is responsible for benzene's unusual stability? A) Presence of sigma bonds only B) Planarity and delocalized π-electrons C) Presence of sp³ hybridized carbons D) Strong dipole moment 27 / 32In Friedel–Crafts acylation, the source of the acyl group is typically: A) Alkyl halide B) Acyl chloride or acid anhydride C) Nitrobenzene D) None of the above 28 / 32Which of the following substituents increases the rate of electrophilic aromatic substitution the most? A) -OCH₃ B) -NO₂ C) -COOH D) -CF₃ 29 / 32Which of the following deactivates benzene towards electrophilic aromatic substitution? A) -CH₃ B) -OCH₃ C) -NO₂ D) -NH₂ 30 / 32Which of the following is true about the effect of substituents on the orientation of electrophilic aromatic substitution? a) Activating groups are ortho-para directors b) Deactivating groups are meta directors c) Halogens are ortho-para directors d) All of the above 31 / 32Which of the following is true about the Friedel-Crafts alkylation reaction? a) It produces an acylated benzene b) It requires a Lewis acid c) It is reversible d) It does not require an electrophile 32 / 32Which of the following is true about the desulfonation of benzenesulfonic acid? a) It is irreversible b) It requires heating in dilute acid c) It produces benzene d) Both b and c Your score isThe average score is 55% 0% Restart quiz
