1. Characteristic Properties of Metals Good electrical conductors and heat conductors. Malleable - can be beaten into thin sheets. Ductile - can be stretched into wire. Possess metallic luster. Opaque as thin sheet. Solid at room temperature (except Hg).

2. Characteristic Properties of Nonmetals Poor conductors of heat and electricity. Brittle - if a solid. Non-ductile. Do not possess metallic luster. Transparent as a thin sheet. Solids, liquids or gases at room temperature.

3. Characteristic Properties of Metalloids Elements that have properties of both metals and nonmetals are called metalloids. They can be shiny or dull and their shape is easily changed. Electricity and heat can travel through metalloids but not as easily as they travel through metals.