Iron undergoes corrosion (rusting) in the presence of water and oxygen to form hydrated iron(III) oxide, Fe2O3⋅xH2O\text{Fe}_2\text{O}_3 \cdot x\text{H}_2\text{O}Fe2O3⋅xH2O.
Which of the following methods prevents iron from rusting by providing both a physical barrier and sacrificial protection?
Coating the iron with plastic
Copper-plating the iron
Galvanising the iron with zinc
Greasing the iron
81 exam-style questions on OCR GCSE Chemistry Improving processes and products. Each one has a worked solution and a mark scheme showing where the marks go.