Past paper 4

• Oxygen and water are need for iron to rust
• Galvanising is when iron is coated with zinc to prevent rusting
• Oxidation is the loss of electrons and reduction is the gain of electrons.
• Oxidation occurs in the rusting of iron
• Methods of preventing iron from rusting are galvanising, sacrificial protection and barrier method
• Barrier is when you coat iron with paint or oil
• Sacrificial protection is when you use magnesium or any other more reactive metal to coat the iron
• Metal conducts electricity because of the delocalised electrons that can move freely
• Aluminum is malleable and it doesn’t react with drinks
• Aluminum can’t be extracted by heating aluminium oxide because Alumium is too high in the reactivity series and the temperature needed is too high
• Magnesium burns with a bright white flame
• Silver is most likely to be found as an uncombined element because its unreactive
• Alloys are harder than pure metals because they’re made up of different sized elements so the layers aren’t even
• Copper causes brown coating
• there is no change on magnesium because magnesium cannot displace itself