(i) What is the name of the main compound in rust?
(ii) Why does the nail in tube 1 not rust?
(iii) What is the purpose of the layer of oil in tube 2?
(b) Zinc can be used to coat iron nails to prevent them from rusting.
(i) What is the name of this process?
(ii) If the layer of zinc on the nail is scratched, sacrificial protection prevents the iron from rusting.
Explain, with the help of two ionic half-equations, how this type of sacrificial protection works.
Use symbols from the box in your equations. You may use each symbol once, more than once or not at all.
Fe Zn Fe2+ Zn2+ e– + – ??
