An engineer investigated the corrosion of buried steel (iron) gas pipelines under two different conditions over a period of six months.
The observations are recorded in the table below:
| Pipeline | Setup | Observation after six months |
|---|---|---|
| Pipeline X | Steel pipe connected to a block of magnesium | The magnesium block has significantly corroded and decreased in mass, but the steel pipe remains undamaged. |
| Pipeline Y | Steel pipe connected to a block of copper | The copper block is completely unchanged, but the steel pipe has heavily rusted. |
Explain these observations.
Practise Edexcel GCSE Chemistry Transition metals, alloys and corrosion with exam-style questions for Foundation and Higher tier. 97 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
