Properties of Metals and Non metals -3

1. What is the difference between thermal conductors and electrical conductors.
2. Cooking utensils are made of iron and copper.Why?
3. What are insulators?
4. Name one non metal which is good conductor of electricity and write its one use.
5. Name the poorest metal conductor.
6. Name the third best conductor of electricity.
7. Silver being the best conductor of electricity is not used in electrical wires.Why?

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