question_answer

\[C{{H}_{3}}{{(C{{H}_{2}})}_{4}}C{{H}_{3}}\xrightarrow[773K,10-20atm]{Cr{{O}_{3}}/A{{l}_{2}}{{O}_{3}}}A\xrightarrow[{}]{B{{r}_{2}}/Fe}B\] \[\xrightarrow[ether]{Mg}C\xrightarrow[{}]{{{H}_{2}}O}D\] What is D?

A)

B)       

C)   

D)

Correct Answer: A

Solution :

: Benzene can be prepared by cyclisation of long chain alkanes on heating at \[500-550{}^\circ C\] under high pressure in presence of catalyst \[Cr{{O}_{3}}\]supported on alumina or \[Pt-A{{l}_{2}}{{O}_{3}}\](i.e., catalytic reforming). \[\underset{n-hexane}{\mathop{{{C}_{6}}{{H}_{14}}}}\,\underset{at\,high\,pressure}{\mathop{\xrightarrow[773K]{Cr{{O}_{3}}/A{{l}_{2}}{{O}_{3}}}}}\,\underset{(A)}{\mathop{{{C}_{6}}{{H}_{6}}}}\,+4{{H}_{2}}\]