Free Benzene and Aromatic Compounds MCQs with Answers
172 Benzene and Aromatic Compounds MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Benzene has a planar ring of delocalised π electrons, giving aromatic stability and equal carbon-carbon bond lengths. The topic covers resonance, electrophilic substitution reactions such as nitration, halogenation, sulphonation and Friedel-Crafts reactions, along with substituent effects and the distinction between substitution in benzene and addition in ordinary alkenes.
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172 questions · page 5 of 9
- A. They are resistant to react with oxygen
- B. They have a cyclic structure
- C. They have a high percentage of Carbon
- D. They have a high percentage of hydrogen
Explanation: Aromatic compound burn with sooty flame because they have a ring structure of carbon atom.
Correct answer: They have a high percentage of Carbon- A. Pyridine
- B. Payroll
- C. Furan
- D. Piperidine
Explanation: Piperidine is an organic compound with the molecular formula (CH2)5NH. This heterocyclic amine consists of a six-membered ring containing…
Correct answer: Piperidine- A. NO2
- B. COOH
- C. NH2
- D. COR
Explanation: This is correct because -NH₂ is an electron-donating group due to its +M (resonance) effect.
Correct answer: NH2- A. 1
- B. 2
- C. 3
- D. 4
Explanation: Anthracene is a polycyclic aromatic hydrocarbon consisting of three benzene rings fused together in a linear arrangement.
Correct answer: 3- A. C6H6
- B. C6H6+ CH3Cl
- C. C6H5C2H5
- D. C6H5Cl and CH3Cl
Explanation: In the Friedel-Crafts reaction for toluene synthesis, anhydrous AlCl3 acts as a catalyst and requires the presence of benzene and CH3Cl.
Correct answer: C6H6+ CH3Cl- A. Aldehyde
- B. Acetophenone
- C. Benzyl Chloride
- D. Benzophenone
Explanation: The reaction of benzene with acetyl chloride(CH3COCl) in the presence of a catalyst like aluminum chloride (AlCl₃) is known as the…
Correct answer: Acetophenone- A. II, III and IV
- B. II and III
- C. I and IV
- D. I, II and IV
Explanation: -CHO and -COOH are meta (3,5) directing groups as they are electron withdrawing groups in nature.
Correct answer: II and III- A. Cl+
- B. Cl-
- C. Cl
- D. FeCl3
Explanation: In the chlorination of benzene, the electrophile is the chloronium ion (Cl+), which is formed in the presence of a Lewis acid like FeCl3.
Correct answer: Cl+- A. Deactivating
- B. Neutral
- C. Activating
- D. All of these
Explanation: Activating groups are most likely to be ortho, para directing as they donate electrons to the benzene ring, increasing its reactivity.
Correct answer: Activating- A. Alkylation
- B. Acylation
- C. Halogenation
- D. Nitration
Explanation: Benzene can be converted to acetophenone (methyl phenyl ketone) by Friedel-Crafts acylation.
Correct answer: Acylation- A. Addition
- B. Substitution
- C. Polymerization
- D. Aromatization
Explanation: Benzene does not undergo polymerisation reaction due to the aromaticity of the ring.
Correct answer: Polymerization- A. Baeyer reagent
- B. Lucas Test
- C. Decolorization of Br2 in CCl4
- D. Orange red colour with CH4/AlCl3
Explanation: Option D is correct.When aromatic hydrocarbons are treated with chloroform and aluminum chloride, orange to red colours are obtained.
Correct answer: Orange red colour with CH4/AlCl3- A. Meta directing and deactivating group
- B. Ortho-para directing and deactivating group
- C. Ortho-para directing and activating group
- D. Ortho directing and activating only
- E. Para directing and deactivating only
Explanation: The explanation for this question will be added soon.
Correct answer: Ortho-para directing and activating group- A. Cyclohexane
- B. Hexane
- C. Phenol
- D. Benzoic Acid
- E. Hexene
Explanation: The explanation for this question will be added soon.
Correct answer: Cyclohexane- A. 2
- B. 3
- C. 6
- D. 4
Explanation: Option A is correct since benzene is a resonance hybrid of these two structures shown in the image: Option B is incorrect since it states…
Correct answer: 2- A. Aliphatic
- B. Aromatic
- C. Alicyclic
- D. None of these
Explanation: Aromatic compounds burn with sooty flame because they have a ring structure of carbon atoms.
Correct answer: Aromatic- A. Naphthalene
- B. Phenanthrene
- C. Anthracene
- D. Triphenylmethane
Explanation: The structure of Triphenylmethane is as follows:
Correct answer: Triphenylmethane- A. Dil HCL
- B. Ethyl alcohol
- C. Acetic acid
- D. Acetyl chloride
Explanation: In aniline, the amino group is an electron-releasing group. It activates the benzene ring towards an electrophilic aromatic substitution…
Correct answer: Acetyl chloride99. Which sequence of reaction conditions should be used to produce the compound below from benzene?
- A. AlCl3 / Cl2 ; H2 / Rh / C
- B. Cl2 / UV light ; H2 / Rh / C
- C. H2 / Rh / C ; AlCl3 / Cl2
- D. HCl ; H2 / Rh / C
Explanation: A would be the answer as we have electrophilic substitution taking place involving the formation of a Cl+ ion which is formed via the…
Correct answer: AlCl3 / Cl2 ; H2 / Rh / C- A. AlCl3
- B. NaOH
- C. Chlorobenzenes
- D. Cumene
Explanation: Sodium benzoate is converted to benzene by heating with a mixture of NaOH and CaO.
Correct answer: NaOH