5. metallic bonding Flashcards
define
Metallic Bonding
The electrostatic attraction between a fixed lattice of positive ions and a sea of delocalised
electrons.
explain the structure of metalic bonding
metalic bonding
The position of the positive ions is fixed. They produced a regular repeating structure that is
classified as a giant metallic lattice.
In a giant metallic lattice:
- Delocalised electrons are spread throughout the structure. (Just like in an ionic compound, the attraction within a metal is in all directions)
- These are able to move within the structure
- It is impossible to tell which electron originated from which particular ion.
- Over the whole structure, the charges must balance.
what are the three
Properties of metals
- High melting and boiling points
- Good electrical conductors
- Malleable and Ductile
explain why metals have
High melting and boiling points
The electrons are free to move throughout the entire structure, but the positive ions are fixed in
the lattice.
The metallic bonds between the positive metal ions and the delocalised electrons are very
strong.
High temperatures are needed to break the metallic bonds and move the ions from the fixed
points within the lattice.
(the greater electron density (the more electrons that get delocalised) the stronger the
attraction in the metallic bond. Leads to a higher melting/boiling point)
explain why metals have
Electrically conductive
The delocalised electrons can move freely anywhere within the metal lattice allowing them to
conduct electricity by carrying the electrical charge.
explain why metals are
Malleable and Ductile
Malleable
Malleable means that the metal can be hammered into shape.
The atoms are able to roll over each other into new positions without disrupting the metallic
bonds.
Ductile
The reasoning for a metal being malleable is the same reason for it being ductile.
The atoms are able to roll over each other into new positions without disrupting the metallic
bonds.
