Ionic bonding: (eg. sodium chloride, mgO, aluminium oxide, Al2O3)
- Formed when metallic atom transfers electrons to non-metallic atom.
- have high melting point and boiling point
- soluble in water but insoluble in organic solvent
- contain a giant lattice in which the oppositely charged ions are held by strong electrosatic attraction.
- ionic compound has a lattice structure held tgt by strong ionic bonds between ions. A lot of energy is needed to break these bonds. Thus high mp and bp.
- most of them exist as solids at room temperature
- some can be used as refractories (heat resistant materials with very high melting point)
- in solid state, ions are arranged in an orderly manner in the crystal lattice by strong electrostatic attraction. Thus, the ions are not free to move about and cannot conduct electricity
- In molten or aqueous state, the electrostatic attraction is weakened and the ions are not bounded to each other. Thus, the ions are free to move about and electricity can be conducted.
- The sharing of electrons equally between atoms of non metals, in order to gain the electronic configuration of an inert/noble gas.
Simple molecular structure:
- low melting and boiling point (volatile)
- soluble in organic solvent but insoluble in water
- do not conduct electricity AT ALL
- exists as molecules
- cannot conduct electricity as it does not have ions or delocalised electrons which can move about to conduct electricity
- all the electrons are either used up during bonding or are located in the shell, therefore no valence electrons.
- low mp and bp as the attractive forces between…