Metallic Bonding

MetalsLook at the Periodic Table…75% of elements are metals!

MetalsO They can vary a lot…

General Properties of Metals

DenseMalleable

DuctileGood conductors of heat and

electricityShiny Lustre

Silver in colour

Any exceptions?

Structure of MetalsMetal atoms tend to lose their valence

electrons (outer electrons) to form positively charged ions.

Metals consist of a lattice of these ions surrounded by a ‘sea’ of delocalised

electrons.

Summary

Metallic Bonding

The structure of metalPhysical Properties Reasons

High melting and boiling points Strong forces of attraction between the ‘sea’ of negatively charged electrons and the positively charged metal ions.

Good conductor of heat and electricity (in solid or molten state)

Presence of free electrons carries heat and electricity energy.

Malleable (hammered into sheets)Ductile (drawn into wires)

Layers of metal atoms can slide over each other without disrupting the metallic bonding. Hence, metallic bonds are strong and flexible.

Lustrous surface Presence of delocalised electrons at the surface

Metallic Bonding