Which of the following is a characteristic of ionic compounds?

Ionic compounds are known for their high melting and boiling points, which is due to the strong electrostatic forces of attraction between the oppositely charged ions that compose the compound. These forces, called ionic bonds, require a significant amount of energy to break, resulting in the high thermal stability of these substances.

In solid form, ionic compounds typically do not conduct electricity as the ions are fixed in a lattice structure and are not free to move. However, when dissolved in water or melted, the ions are released, allowing the compound to conduct electricity. Therefore, the ability to conduct electricity is dependent on the state of the compound rather than a general characteristic.

Ionic compounds do not solely exist as gases; they are usually found as solids at room temperature and can form various structural forms. Given these characteristics, it is clear why high boiling points are a defining trait of ionic compounds.