Question

Name the hydrocarbon which when heated to a temperature of about 773 K under high pressure in the presence of $C{r}_2{O}_3/A{l}_2{O}_3$ catalyst gives benzene.

• A. n-pentane
• B. n-hexane
• C. n-pentane
• D. n-octane

Answer 1

The correct option is B n-hexane

Aromatization: The n-alkanes with 6 or more C atoms, on heating to 773 K at 10-20 atm pressure in the presence of oxides of V/Mo/Cr get dehydrogenated and cyclised to form benzene and its derivatives.
$\underset{\text{n-hexane}}{C_6{H}_{14}}\underset{△\left(773K\right)}{\overset{C{r}_2{O}_3/A{l}_2{O}_3,10-20atm}{\to }}\underset{\text{benzene}}{C_6{H}_6}$