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1 Organic Chemistry MCQs

When benzene is substituted by halogens, which halogen gets position 1 in naming the compound?

  • Bromine
  • Chlorine
  • Fluorine
  • Iodine
0 Comments
Correct Answer: C. Fluorine

Explanation:

In organic chemistry, when more than one halogen atom is attached to a ... Read More Details

2 Organic Chemistry MCQs

Benzene was discovered by Michael Faraday during the destructive distillation of vegetable oil in the ?

  • Presence of oxygen
  • Presence of hydrogen
  • Absence of oxygen
  • Presence of excessive oxygen
0 Comments
Correct Answer: C. Absence of oxygen

Explanation:

Benzene (C₆H₆) was discovered by Michael Faraday in 1825 during his experiments on ... Read More Details

3 Organic Chemistry MCQs

How many moles of hydrogen gas (H₂) react with benzene in the presence of a platinum catalyst?

  • 2
  • 3
  • 4
  • 6
0 Comments
Correct Answer: B. 3

Explanation:

Benzene (C₆H₆) is an aromatic compound with six carbon atoms connected in a ... Read More Details

4 Organic Chemistry MCQs

What is the resonance energy of benzene?

  • 150.5 kJ/mol
  • 250.5 kJ/mol
  • 150.5 cal/mol
  • 250.5 cal/mol
0 Comments
Correct Answer: A. 150.5 kJ/mol

Explanation:

Benzene (C₆H₆) is an aromatic compound with a unique stability that cannot be ... Read More Details

5 Organic Chemistry MCQs

Which catalyst is used to prepare benzene from acetylene at 70°C?

  • Cr₂O₃ + Al₂O₃ + SiO₂
  • Raney nickel
  • Organo-nickel
  • Ni (250–300°C)
0 Comments
Correct Answer: C. Organo-nickel

Explanation:

Benzene can be synthesized from acetylene (ethyne) by a process known as trimerization, ... Read More Details

6 Organic Chemistry MCQs

Which method does not give benzene?

  • Sodium benzoate + soda lime
  • Phenol + Zn dust
  • Chlorobenzene + NaOH (360°C, 150 atm)
  • Benzene sulfonic acid + steam
0 Comments
Correct Answer: C. Chlorobenzene + NaOH (360°C, 150 atm)

Explanation:

Several chemical methods are used to prepare benzene from different organic compounds. Understanding ... Read More Details

7 Organic Chemistry MCQs

When bromine reacts with benzene in the presence of sunlight, what will happen?

  • The benzene ring will break
  • Substitution reaction will occur
  • Addition reaction will occur
  • No reaction will occur
0 Comments
Correct Answer: C. Addition reaction will occur

Explanation:

Benzene (C₆H₆) is an aromatic compound that generally undergoes electrophilic substitution reactions rather ... Read More Details

8 Organic Chemistry MCQs

During the sulfonation of benzene, concentrated H₂SO₄ generates which electrophile?

  • HSO₄⁻
  • SO₂
  • SO₃
  • H⁺
0 Comments
Correct Answer: B. SO₂

Explanation:

Sulfonation of benzene is an example of an electrophilic aromatic substitution (EAS) reaction ... Read More Details

9 Organic Chemistry MCQs

Which compound will readily undergo sulfonation?

  • Benzene
  • Nitrobenzene
  • Toluene
  • Chlorobenzene
0 Comments
Correct Answer: C. Toluene

Explanation:

Sulfonation is an electrophilic aromatic substitution (EAS) reaction in which a –SO₃H group ... Read More Details

10 Organic Chemistry MCQs

Which one of the following statements is not correct about benzene?

  • During hydrogenation, 208 kJ/mol of energy is released.
  • The C–H bond length in benzene is 1.09 Å.
  • The molecular mass of benzene is 78.108 g/mol.
  • The resonance energy of benzene is 150.5 kcal/mol.
0 Comments
Correct Answer: B. The C–H bond length in benzene is 1.09 Å.

Explanation:

Benzene (C₆H₆) is an aromatic hydrocarbon consisting of six carbon atoms arranged in ... Read More Details

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