Rust

Aims

Pupils should gain an understanding of:

• How some elements combine through chemical reactions to form compounds;
• The fact that compounds have a definite composition, and you can represent compounds by formulae;
• Mass being conserved when chemical reactions take place;
• Some chemical reactions not being useful e.g. corrosion of iron;
• How acids in the atmosphere can lead to corrosion of metal.
• The fact that most metals corrode, some more than others;
• When chemicals react there is no change of mass;
• The fact that for iron to rust both oxygen and water are needed;
• How rusting can be prevented by protecting a metal surface from oxygen and water;
• The fact that acid gases in the atmosphere speed up corrosion.