Difference between Metals and Non-Metals

METALS

NONMETALS

Metals have 1 to 3 electrons in their valence shell

Nonmetals have 4 to 8 electrons in their valence shell

They form positively charged ions called cations

They form negatively charged ions called anions

They are generally solid (except Mercury and Gallium)

They exist in all 3 states of matter

They are hard and non-brittle - cannot break easily (except Sodium, Potassium, Lead)

They are hard but brittle

They are generally heavy (except Sodium, Potassium, Magnesium)

They are light

They are good conductors of heat and electricity (except lead)

They are poor conductors of heat and electricity

They can be beaten into thin sheets and are thus malleable

They are not malleable

They can be drawn into thin wires and are thus ductile

They are non ductile

They produce a ringing sound on being struck and are thus sonorous

They are not sonorous

They are generally lustrous and can be polished

They are not lustrous

Metals have high attraction between molecules thus they have high tensile strength

Nonmetals have low attraction between molecules thus they have low tensile strength

They have high degree of compactness and thus high density

They have low degree of compactness and thus low density

Their melting and boiling points are high due to strong intermolecular attraction

Their melting and boiling points are low due to weak intermolecular attraction

They form basic oxides on reacting with oxygen

They form acidic oxides on reacting with oxygen

Examples - Sodium, Potassium, Magnesium, Lithium etc.

Examples - Boron, Carbon, Silicon, Iodine etc.