Route P has 100% atom economy but reaches equilibrium very slowly, even with a catalyst. Route Q has 70% atom economy, a fast rate and a by-product that can be sold. Why might Route Q be chosen?
Route Q wastes fewer reactant atoms than Route P
Route Q's fast rate and useful by-product offset its waste
Route P's catalyst will raise its atom economy over time
Route P's slow rate means its atom economy is really low
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.