Copper can be obtained by adding scrap iron to copper sulfate solution.
Fe(s)+CuSO4(aq)→FeSO4(aq)+Cu(s)\mathrm{Fe(s)} + \mathrm{CuSO_{4}(aq)} \rightarrow \mathrm{FeSO_{4}(aq)} + \mathrm{Cu(s)}Fe(s)+CuSO4(aq)→FeSO4(aq)+Cu(s)
Relative formula masses: FeSO4=152\mathrm{FeSO_{4}} = 152FeSO4=152, Cu = 63.5
State what is meant by the atom economy of a reaction.
Name the by-product of this reaction.
Calculate the atom economy for making copper by this reaction. Use the equation: atom economy=relative formula mass of desired productsum of relative formula masses of all products×100\displaystyle \text{atom economy} = \frac{\text{relative formula mass of desired product}}{\text{sum of relative formula masses of all products}} \times 100atom economy=sum of relative formula masses of all productsrelative formula mass of desired product×100. Give your answer to three significant figures.
Give one reason why chemists want reactions to have a high atom economy.
Hydrogen reacts with chlorine to make hydrogen chloride. This is the only product. Give the atom economy of this reaction.
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.