network solid
Most ionic solids cannot conduct electricity in the solid phase. They only do so in the liquid phase. While they are solid, the ions in the ionic solid are fixed in their lattice so cannot move to conduct electricity whereas in the liquid phase, the ions are free and mobile and can act as charge carriers for electricity.
No, camphor does not conduct electricity. It is a type of organic compound, so it cannot ionize to conduct electricity.
it is watretight and doesnt conduct heat or electricity ie fairly unreactive
Ionic compounds generally dissolve in water dissociating to give ions that are free to move and conduct electricity. Molten ionic compounds also have free ions and conduct electricity. Ionic compounds generally do not conduct electricity in the solid form.
Assuming you mean electrical conductor / insulator, most bar magnets are made of solid metal, either iron, neodymium or an alloy of aluminium nickel and cobalt, so they conduct electricity. There is one type of magnet called a ferrite magnet which does not conduct electricity - they are the type often found in loudspeakers.
gold
One type of material that does not conduct heat or electricity is a ceramic material, such as glass or porcelain. These materials have a high electrical resistance and low thermal conductivity, which prevents the flow of heat or electricity through them.
The best conductor for heat and electricity is any type of metal element.
It depends on the type of metal. The ability of a metal to conduct electricity is one trait that identifies a metal. For example, copper can conduct electricity very well (better than most metals).
ionic compounds
This depends on the type of foam. There have been made foam that actually conduct electricity. This is a choice made in the manufacturing of the foam. Most foam in mattresses and the like does not conduct electricity. Moisture however can change the mattresses conductivity drastically.
It depends on the type of food. Some do, some don't.