C3.9/10 - Metals + metallic bonding

-occurs between metals only

• giant lattices of positively charged ions - arranged in regular patterns on top of each other

• outer electrons of metals become delocalised • forming positive metal ions • a sea of electrons is formed by the free electrons to surround the ions • strong electrostatic attraction occurs between the electrons + ions = bonded

• high melting/boiling points • malleable • good conductors of heat/electricity

-due to strong metallic bonds

-as atoms are arranged in regular layers that can slide over each other

• due to their delocalised electrons - they can carry charge through the metal

• held together by giant metallic structure • atoms are arranged in tightly packed layers • so they can slide over each other • making iron soft

are softer

• a mixture of 2/more elements - 1 element must be a metal

• iron mixed with carbon atoms • as carbon atoms are a different size • they do not form regular layers • making it harder for them to slide over each other • making steel hard

• as the other elements in the alloy will be a different size to the metal atoms • they will not form a regular layer • the layers will not be able to slide over each other • making it a harder material

• the delocalised electrons in the lattice cause it to move out of shape • when struck, metal atoms can slip past one another • making them malleable

they can be drawn into wires

• their giant structures • means that their electrostatic forces extend in all directions • so it takes a lot of energy to separate them and break down the lattice

• their delocalised electrons flow through the metal - they carry charge/energy easily