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Write the chemical equation for the following.
Balz-Schiemann reaction
Answer
Answer
Official answer keyEquations: $\mathrm{C_{6}H_{5}N_{2}Cl} + \mathrm{HBF_{4}} \xrightarrow{\text{273-278}\text{ }\text{K}} \mathrm{C_{6}H_{5}N_{2}BF_{4}} + \mathrm{HCl}$ $\mathrm{C_{6}H_{5}N_{2}BF_{4}} \xrightarrow{\text{heat}} \mathrm{C_{6}H_{5}F} + \mathrm{BF_{3}} + \mathrm{N_{2}}$
Product: fluorobenzene
A diazonium chloride is treated with fluoroboric acid; the diazonium fluoroborate formed is heated to give fluorobenzene.
From ISC 2026 Specimen Chemistry Paper 1, question 11(ii).