(a) High melting points and boiling points.
- Ions held by strong electrostatic forces.
- Needs a lot of energy to overcome these forces.
(b) Conduct electricity when in molten or aqueous solution.
- In solid, ions are fixed in positions and do not move freely.
- In molten state or aqueous solution, the ions can move freely.
(c) dissolve in water(d) does not dissolve in organic solvents.