SC13a - Where are Transition Metals found, on the periodic table?
In the middle of the periodic table, between groups 2 and 3
SC13a - Describe some typical physical properties of transition metals.
- Lustrous (when polished)
- Good conductors of heat and electricity
- High melting points and densities (compared to groups 1 and 2)
SC13a - Describe some typical chemical properties of transition metals.
- Usually form coloured compounds (colour decided by the ion involved e.g. copper forms blue compounds)
- Chemical catalysts
SC13b - What is corrosion?
When a metal continuously oxidises over time becoming weaker
SC13b - What are the two requirements for corrosion to occur?
Oxygen (in air typically) and water
SC13b - What is rusting?
The corrosion of Iron (or steel)
SC13b - What is oxidation in terms of electrons and oxygen?
The loss of electrons and/or the gain of oxygen
SC13b - How does sacrificial protection work?
- A more reactive metal is attached to Iron or Steel.
- The oxygen and water are going to react with the more reactive metal instead, protecting the iron and steel
SC13b - Which metals are typically involved in sacrificial protection?
Zinc or magnesium, protecting iron or steel from rusting
SC13b - What makes a metal more or less reactive?
How easily its able to loose its outer shell electrons (this is a combination of how many there are and how far away from the nucleus they are)
SC13c - For what two main reasons may a metal be electroplated?
- To improve its appearance
- To improve its resistance to corrosion or rusting
SC13c - What process is used to electroplate a metal?
SC13c - What is galvanising?
Coating iron or steel with zinc to protect it.
SC13c - Which two methods can be used to galvanise an object?
Dipping it in molten zinc or electroplating
SC13c - When electroplating, what would you use as the anode and cathode?
- Cathode will be the object you are plating
- Anode will be the metal you are plating it with.
SC13d - What is an alloy?
A mixture of a metal with one or more other (not necessarily metal) elements
SC13d - Why are alloys stronger than pure metals [4 marks]
- In a pure metal all the atoms are the same size in a regular structure
- his allows layers to slide over each other easily
- In an alloy, the atoms are different sizes in an irregular structure
- This means layers cannot slide over each other as easily
SC13e - Name some uses of gold copper and aluminium linked to their properties that suit its use.
- Memory chips - Good conductor of electricity
- Jewellery - Lustrous
- Wires - Ductile
- Coins - Cheap and malleable
- Overhead cables - Low density
SC13e - Name some uses of magnalium, brass and nitinol linked to their properties that suit its use.
Magnalium (Magnesium and aluminium):
- Lightweight mechanical parts
- Low density
- High strength
Brass (Copper and zinc):
- Plug in points
- Corrosion resistant
- Good conductor of electricity
Nitinol (Nickel and Titanium):
- Braces and glasses frames
- Shape memory allows it to have 2 shapes depending on pressure or temperature.