Iron is heated in air. Iron oxide is produced.
Balance the equation for this reaction.
Fe+O2→Fe2O3\text{Fe} + \text{O}_2 \rightarrow \text{Fe}_2\text{O}_3Fe+O2→Fe2O3
The mass of the solid increases when the iron is heated in air. Explain why.
40 exam-style questions on AQA GCSE Chemistry 3.1 Chemical measurements, conservation of mass and the quantitative interpretation of chemical equations, covering 3.1.1 Conservation of mass and balanced chemical equations, 3.1.2 Relative formula mass, 3.1.3 Mass changes when a reactant or product is a gas, and 3.1.4 Chemical measurements. Each one has a worked solution and a mark scheme showing where the marks go.