Ionic, Covalent, and Metallic Bonding
IonicSubstances with Ionic bonds normally have a powdery or granular appearance. They also dissolve in water which can conduct electricity. They also conduct electricity as a liquid, if it is melted, but it's hard to melt. As a solid it cannot conduct electricity.
Substances that have covalent bonds normally have a powdery and granular appearance. Most of the time they dissolve in water, but when it is it doesn't conduct electricity. In any form it does not conduct electricity, even though it melts.
Substances with metallic bonds appear very shiny, and doesn't dissolve is water. When it melts it takes a lot of heat and it still conducts electricity. It conducts electricity in any form.