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Chemical synthesis — Question 9

QCAA 2023, Paper 2 · 4 marks

Q9 · 2023 · Paper 2Unclassified4 marks

QUESTION 9 (4 marks)

Aspirin (C9H8O4) can be produced from a reaction between salicylic acid (C7H6O3) and acetic anhydride (C4H6O3) with ethanoic acid being a minor product.

C7H6O3(s)+C4H6O3(aq)→C9H8O4(s)+C2H4O2(aq)\mathrm{C}_{7}\mathrm{H}_{6}\mathrm{O}_{3}\mathrm{(s)}+\mathrm{C}_{4}\mathrm{H}_{6}\mathrm{O}_{3}(aq) \rightarrow C_{9}\mathrm{H}_{8}\mathrm{O}_{4}\mathrm{(s)}+\mathrm{C}_{2}\mathrm{H}_{4}\mathrm{O}_{2}\mathrm{(aq)}

Calculate the mass of salicylic acid required to produce 8.25 g of aspirin if the percentage yield of the reaction is 60%. Show your working.

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