A reaction has 100% atom economy but only 70% yield. Which explanation is possible?
The balanced equation forms a waste product
Some reactant remains unreacted
The catalyst was used up, so less product formed
Some product was converted into energy
51 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.