Metals : 1. They are electropositive elements. 2. Their oxides are basic. 3. They tend to lose electrons & form positive ions. 4. They are lustrous , malleable & ductile except Hg which is the only liquid metal. 5. Elements of group IA , IIA , some elements of IIIA – VIA & all transition elements are metals. 6. They are good conductors of heat & electricity.
Non - Metals : 1. They are electronegative elements. 2. Their oxides are acidic. 3. They tend to gain electrons & form negative ions. 4. They are not lustrous , malleable & ductile. 5. Majority of elements of p-block are non metals. 6. They are bad conductors of heat & electricity.
Mettaloids : 1. They exhibit metallic as well as non-metallic characters. 2. Their oxides are amphoteric ( basic as well as acidic ) in nature. 3. They are concentrated between the metals & the nonmetals in the periodic table.