9 - Metals Flashcards
Why is Aluminium almost as reactive as Magnesium, yet takes much longer to react?
It has a thin protective layer of Aluminium Oxide that take time to wear away
Name all the metals and hydrogen in their order of reactivity from highest to lowest
Potassium
Sodium
Lithium
Calcium
Magnesium
Aluminium
(Carbon)
Zinc
Iron
(Hydrogen)
Copper
Silver
Gold
Please Send Little Charlies Monkeys And Zebras In Hinged Cages Guarded Safely
What is the reactivity series?
The order of reactivity of a few selected metals and hydrogen
Which metals react with cold water?
Name them in order of reactivity from higherst to lowest
- Potassium
- Sodium
- Lithium
- Calcium
Which metals react with steam and acids only?
Name them in order of reactivity from higherst to lowest
- Magnesium
- Aluminium
- Zinc
Which substances react with acids only?
Name them in order of reactivity from highest to lowest
- Iron
- Hydrogen
Which substances do not react?
Name them in order of reactivity from higherst to lowest
- Copper
- Silver
- Gold
When does a displacement reaction occur?
When a metal reacts with an ion of another metal, and the metal is more reactive than the ion.
What is a displacement reaction (for metals)?
A reaction where a more reactive metal reduces a metal ion, making it gain electrons and form a metal atom as well
What is the link between displacement and redox reactions?
Displacement reaction are always redox reactions
In which states do metals conduct electricity?
Solids and liquids
What is the word equation for the corrosion of iron?
Aka Rusting
Iron + Oxygen gas + Water —> Hydrated Iron (III) Oxide
What are the methods to prevent rusting?
- Painting
- Greasing
- Plastic covering
- Electroplating
- Galvanisation
What is Galvanisation?
Iron to be protected is coated with a layer of zinc.
This can be done by electroplating or dipping it into molten zinc
Def. Barrier Method
Physical barrier to prevent corrosion
|Eg. Greasing, painting, or plastic coating
Def. Sacrificial protection
A more reactive metal is oxidised in preference; it loses its electrons easier
This means another meal can be used to prevent the first from rusting
Def. Alloy
A mixture of a metal with other elements
What alloys are you required to know?
Brass - Mixture of copper and zinc
Stainless Steel - Mixture of iron with other elements such as chromium, nickel and carbon
What are the advantages of alloys?
- They can be harder and stronger than pure metals
- They can be more useful than normal metals e.g resistant to corrosion
Why is stainless steel used in cutlery?
- Hardness
- Resistance to rusting
Why are alloys harder and stronger than pure metals?
They have ions of different sizes so layers of ions can’t slide over each other as easily
Meaning they aren’t as malleable
What are the uses of aluminium?
Explain the properties that allow it to be useful
- Food Containers - Corrosion resistant
- Aircraft - Low density
- Overhead cables - Good electrical conductor & low density
What are the uses of stainless steel?
Explain the properties that allow it to be useful
- Cutlery - Corrosion resistant
What are the uses of Zinc?
Explain the properties that allow it to be useful
- Galvanising steel - To prevent corrosion through sacrificial protection
- Making brass - Increases hardness
What are the uses of Copper?
Explain the properties that allow it to be useful
- Making brass - Increases hardness
- Electrical wires - Good electrical conductor
