There are a lot of properties of ionic compounds to explain.
The most characteristic ones are:
- High melting points
- Hard and brittle
- Electrical conductivity
All of these can be explained by the forces in ionic compounds.
The forces that maintain the ions together are electrostatic forces, which come from the charged ions with opposite signs.
Electrostatic forces are very strong, so and in ions this occur in a crystal lattice, so we need a lot of energy to break this attraction. Because of that, we need a high temperature to make it has enough energy to break this attraction and melt.
This strong attraction also makes the ionic compounds hard to break, because we will need a lot of force to break the ions appart. However, once enough force is applied, its lattice structure is shifted and ions with same charge becomes close to each other, making a repulsive force that breaks them appart, giving them the brittle property.
An electrical conductivity happens when there are free charges in a system. The ionic compounds are composed by charged particles, so if they are free to move, they will conduct electricity. So, when the compound is melted of dissolved, the charged ions, that once were together by the electrostatic force, now can conduct electricity.I have finished answering the question.