In one stage of the Contact Process for making sulfuric acid, sulfur dioxide, SO2\text{SO}_2SO2, is reacted with oxygen to produce sulfur trioxide, SO3\text{SO}_3SO3.
2SO2+O2⇌2SO3 2\text{SO}_2 + \text{O}_2 \rightleftharpoons 2\text{SO}_3 2SO2+O2⇌2SO3Calculate the minimum volume of air, measured at room temperature and pressure, required to react completely with 1280 g of sulfur dioxide.
Assume that air contains 20% oxygen by volume.
(Relative atomic masses, ArA_rAr: S = 32, O = 16; 1 mol of gas occupies 24 dm3 at room temperature and pressure)
157 exam-style questions on Edexcel GCSE Chemistry 6.2 Quantitative analysis, covering 6.2.1 Concentration in mol dm⁻³ and titration calculations, 6.2.2 Percentage yield and why actual yield falls short, 6.2.3 Atom economy of a reaction, 6.2.4 Choosing a reaction pathway, and 6.2.5 Molar volume of gases and Avogadro's law. Each one has a worked solution and a mark scheme showing where the marks go.