Questions on our topic:
Why don’t some metals rust?
Some metals like aluminium have a thin layer known as aluminum oxide. It forms on the metals outer surface and acts like a rust-preventing shield.
Why does it take some things longer to rust than others?
Because it would depend on what the object is added into.
Why do materials rust?
Metals rust because in some way, they are exposed to air and water for a certain period of time.
What does rust look like?
Rust is a iron oxide that looks brownish-orange in colour. It is brittle, soft, weak and flaky.
How can rust be prevented?
There are many ways to prevent rust from forming. One way to stop it is to paint over the object that is able to rust. This helps because it acts as a shield and stops the oxygen from affecting the metal. Plastic also helps to keep the oxygen away from the material.
How does Rust work?
Iron and steel rust when they come into contact with water and oxygen. Both water and oxygen are needed for rusting to occur. But aluminium does not because of the thin layer of aluminium oxide that protects it.
Does every type of iron rust?
All irons rust when they come in contact with oxygen. Both air and water are needed for the rusting of iron.
Are there different types of rust?
Yes, there are different kinds of rust. There are 2 types of rust. The first on is FeO and the next one is Fe2O3. The second one, Fe2O3 has two different crystal structures: trigonal (hematite) and cubic (magnetite).
Aim: To find the best way to prevent rust.
- Steel wool (x3) One already painted
- Water-based paint
- Salt water
- Beaker x3
- Measure out 150mL of salt water in each beaker.
- Wrap plastic around one piece of steel wool tightly.
- Place each piece of steel wool in each beaker.
- Wait until Monday.
- Observe the results. Was our hypothesis (prediction) correct?
Fair test table: