extra properties/bonding Flashcards
properties of metallic bonding/lattice structure
- range of mp
- always conduct due to delocalised electrons
properties of covalent molecular
- low mp/bp
- no conductivity
propererties of covalent network
- extermely high mp
- do not conduct
- do not dissolve
properties of ionic bonding
- high mp
- cant conduct as solid
- conduct in solition/molten
why do covalent molecules have low mp/bp?
due to the presence of weak attractions between molecules
why do covalent networks have high mp?
due to strong covalent bonding which must be overcome to melt substances
why are solid ionic compounds unable to conduct?
the ions are held in the lattice structure and cannot move
cant move = cant conduct
why can ionic compounds conduct when molten or in solution?
the ionic lattice is destroyed and the ions are free to move
why are the mp of colavent molecular substances low?
only weak attractions between molecules required to be broken to melt
what are the only covalent networks?
- carbon
- silicon
- boron
- silicon dioxide
what covalent network is able to conduct?
carbon in the form of graphite
why must a dc supply be used?
to allow each product to be identified
