Calculate the atom economy for the production of magnesium oxide (MgO{\text{MgO}}MgO) in the following thermal decomposition reaction:
MgCO3→MgO+CO2 \text{MgCO}_3 \rightarrow \text{MgO} + \text{CO}_2 MgCO3→MgO+CO2You must show your working.
(Relative atomic masses, ArA_rAr: C=12\text{C} = 12C=12, O=16\text{O} = 16O=16, Mg=24\text{Mg} = 24Mg=24; Relative formula mass, MrM_rMr: MgO=40\text{MgO} = 40MgO=40)
119 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.