Which statement correctly explains how sacrificial protection prevents the rusting of an iron structure when coated with or connected to a block of zinc?
Zinc is less reactive than iron, so it acts solely as a physical barrier preventing water and oxygen from contacting the iron.
Zinc is more reactive than iron, which means it is more readily reduced than iron, thereby protecting the iron.
Zinc is more reactive than iron, which means it is more readily oxidised than iron, losing electrons in preference to it.
Zinc is less reactive than iron, but the zinc ions formed react with iron to form a protective layer.
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.