NEET2026ChemistryChapterActual
The given flowchart illustrates various methods for the preparation of benzene. Identify the correct set of reagents A, B, and C required for these conversions.
Options
- AA = Red hot iron tube at 873 K; B = Sodalime, ; C = Zn dust,
- BA = Mo₂O₃ at 773 K; B = Sodalime, ; C = Na metal,
- CA = Red hot iron tube at 873 K; B = Aqueous NaOH, ; C = Zn dust,
- DA = Cr₂O₃ at 773 K; B = NaHCO₃ , ; C = warm H₂O
Correct answer
A. A = Red hot iron tube at 873 K; B = Sodalime, ; C = Zn dust,
Step-by-step solution
The given flowchart shows three different methods for the preparation of benzene. Reaction A represents the cyclic polymerization of ethyne. When ethyne is passed through a red hot iron tube at 873 K , it undergoes cyclic polymerization to form benzene. Thus, A is a red hot iron tube at 873 K . Reaction B represents the decarboxylation of sodium benzoate. When sodium benzoate is heated with sodalime (a mixture of NaOH and CaO ), it undergoes decarboxylation to yield benzene. Thus, B is sodalime, . Reaction C repres