Which one of the following reactions does NOT give benzene as the product?
- H-C C-H [at 873 K]red hot Iron Tube
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Answer
(2) [figure]
Solution
(1) Cyclic polymerisation of ethyne in a red hot iron tube at 873 K gives benzene.
(2) Warming benzenediazonium chloride with water gives phenol, not benzene:
C6H5N2+Cl- + H2O warm C6H5OH + N2 + HCl
(3) Decarboxylation of sodium benzoate with sodalime gives benzene:
C6H5COONa + NaOH [ ]CaO C6H6 + Na2CO3
(4) Aromatisation of n-hexane over Mo2O3 at 773 K, 10-20 atm gives benzene.
Answer: (2)