Q8 / 150 · MHT CET 2026 (15 April Shift 1) · Chemistry
Identify the product of reforming reaction of n-hexane in the presence of $\text{V}_2\text{O}_5$ over alumina.
- Correct answerABenzene
- BCyclohexane
- CMethyl benzene
- DPhenol
Solution
Alkanes containing six or more carbon atoms on heating to $773 \text{ K}$ at $10-20 \text{ atm}$ pressure in the presence of oxides of vanadium, molybdenum or chromium supported over alumina get dehydrogenated and cyclised to benzene and its homologues. This reaction is known as aromatization or reforming.
When n-hexane is passed over $\text{V}_2\text{O}_5$ supported on alumina, it undergoes aromatization to form benzene.
$\text{CH}_3-(\text{CH}_2)_4-\text{CH}_3 \xrightarrow{\text{V}_2\text{O}_5 / \text{Al}_2\text{O}_3, 773 \text{ K}, 10-20 \text{ atm}} \text{C}_6\text{H}_6 + 4\text{H}_2$
Answer: Benzene
When n-hexane is passed over $\text{V}_2\text{O}_5$ supported on alumina, it undergoes aromatization to form benzene.
$\text{CH}_3-(\text{CH}_2)_4-\text{CH}_3 \xrightarrow{\text{V}_2\text{O}_5 / \text{Al}_2\text{O}_3, 773 \text{ K}, 10-20 \text{ atm}} \text{C}_6\text{H}_6 + 4\text{H}_2$
Answer: Benzene
Hence, the correct answer is option: 'A'.