Steel ships corrode in sea water. To reduce this, blocks of zinc are attached to the steel hull below the water line.
Part of the reactivity series is shown, with the most reactive metal first:
magnesium, zinc, iron, copper
Name the other metal in the list that could be used instead of zinc for the blocks.
Explain how the zinc blocks stop the steel hull from rusting.
Suggest why the zinc blocks must be replaced regularly.
Suggest why blocks of copper would not protect the hull.
A steel gate is painted. After the paint is scratched, the gate starts to rust where the scratch is. Explain why.
42 exam-style questions on Edexcel GCSE Chemistry 6.1 Transition metals, alloys and corrosion, covering 6.1.1 Properties of transition metals, 6.1.2 Corrosion and its prevention, and 6.1.3 Alloys and the uses of metals. Each one has a worked solution and a mark scheme showing where the marks go.