Conductors, insulators & electrons
Conductors
- A conductor is a material that allows charge (usually electrons) to flow through it easily
- Examples of conductors are:
- Silver
- Copper
- Aluminium
- Steel
- Conductors tend to be metals
Different materials have different properties of conductivity
- On the atomic scale, conductors are made up of positively charged metal ions with their outermost electrons delocalised
- This means the electrons are free to move
- Metals conduct electricity very well because:
- Current is the rate of flow of electrons
- So, the more easily electrons are able to flow, the better the conductor
The lattice structure of a conductor with positive metal ions and delocalised electrons
Insulators
- An insulator is a material that has no free charges, hence does not allow the flow of charge through them very easily
- Examples of insulators are:
- Rubber
- Plastic
- Glass
- Wood
- Some non-metals, such as wood, allow some charge to pass through them
- Although they are not very good at conducting, they do conduct a little in the form of static electricity
- For example, two insulators can build up charge on their surfaces and if they touch this would allow that charge to be conducted away
