CSEC Chemistry · May/June 2011 · Paper 1 · Question Q43

Over time, aluminium articles do not deteriorate in air as do iron articles. Which of the following statements gives the CORRECT reason?

1. (A)Aluminium is higher up in the activity series than iron, therefore it is more resistant to corrosion than iron.
2. (B)Aluminium is lower than iron in the activity series, therefore it reacts less readily with air than iron.
3. (C)Both metals form hydroxide coats but the aluminium hydroxide prevents further reaction while the iron hydroxide does not.
4. (D)Both metals form oxide coats but aluminium oxide prevents further reaction while the iron oxide does not.