Inside a sealed reactor, sulfur dioxide reacts with oxygen. Sulfur dioxide is supplied in excess, so oxygen is the limiting reactant.
2SO2+O2⇌2SO32\text{SO}_2 + \text{O}_2 \rightleftharpoons 2\text{SO}_32SO2+O2⇌2SO3
Each operating cycle uses 3.20 kg of oxygen.
Relative atomic masses: O=16\text{O} = 16O=16, S=32\text{S} = 32S=32.
Calculate, in kg\text{kg}kg, the mass of sulfur trioxide predicted by the balanced equation for one operating cycle.
In one operating cycle, 12.4 kg of sulfur trioxide is separated and collected. Calculate the percentage yield. Give your answer to 3 significant figures.
Even before any sulfur trioxide is removed, the reactor contains less sulfur trioxide than the mass calculated in part (a). Give one reason why, based on the reaction shown in the equation.
104 exam-style questions on AQA GCSE Chemistry 3.3 Yield and atom economy of chemical reactions, covering 3.3.1a Percentage yield, 3.3.1b Theoretical mass of a product, 3.3.2a Atom economy, and 3.3.2b Choosing a reaction pathway. Each one has a worked solution and a mark scheme showing where the marks go.