Chemistry Hydrocarbons NUMS 2019
PMDC Verified Question 29 of 65
Which catalyst is used in oxidation of benzene ring?
A
\( \text{FeBr}_3 \)
B
\( \text{Fe} + \text{Al}_2\text{O}_3 \)
C
\( \text{V}_2\text{O}_5 \)
D
Raney Ni
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option C: \( \text{V}_2\text{O}_5 \)
Concept:

The benzene ring is exceptionally stable and resists normal oxidizing agents (like \( \text{KMnO}_4 \) or \( \text{K}_2\text{Cr}_2\text{O}_7 \)). Harsh catalytic conditions are required to break the ring.

Solution:

  • To forcefully oxidize and cleave the aromatic benzene ring itself, it is heated strongly (around 450°C) with oxygen in the presence of a specific catalyst.


  • Vanadium pentoxide (\( \text{V}_2\text{O}_5 \)) serves as the ideal catalyst for this severe oxidation, ultimately yielding maleic anhydride.


Why other options are incorrect:

  • \( \text{FeBr}_3 \) is a Lewis acid used for halogenation (substitution), not oxidation.


  • Raney Ni is a powerful catalyst for reduction (hydrogenation) of benzene, not oxidation.

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