IGCSE Chemistry 0620/21/O/N/21 Q29
29 Covering iron with zinc prevents the iron from rusting even when the zinc is scratched.
Covering iron with tin prevents the iron from rusting, but when the tin is scratched the iron underneath starts to rust.
Which statement is correct?
A Both tin and zinc prevent iron from rusting by sacrificial protection.
B Both tin and zinc prevent iron from rusting by stopping water and carbon dioxide reaching the iron.
C Tin is more reactive than iron and prevents iron from rusting until it is scratched.
D Zinc loses electrons more easily than iron and prevents iron from rusting by corroding first.