What are the 7 properties of ionic compounds?
Ionic compounds have distinct physical and chemical properties due to their strong electrostatic forces between positively and negatively charged ions. Here are the seven key properties of ionic compounds:
1. High Melting and Boiling Points
Ionic compounds have strong electrostatic forces of attraction between oppositely charged ions. A large amount of energy is needed to break these bonds, resulting in high melting and boiling points. For example, sodium chloride (NaCl) melts at 801°C.
2. Hard and Brittle Structure
Ionic compounds are hard due to the strong attraction between ions in a crystalline lattice structure. However, they are brittle because when force is applied, like charges align and repel each other, causing the crystal to shatter instead of bending.
3. Solubility in Water
Most ionic compounds are soluble in water but insoluble in non-polar solvents like benzene or ether. Water molecules surround and pull apart the ions due to their polarity, dissolving the compound. Examples: NaCl (soluble), AgCl (insoluble).
4. Electrical Conductivity in Liquid State
In their solid state, ionic compounds do not conduct electricity because the ions are fixed in place. However, in the molten state or aqueous solution, the ions are free to move, allowing the substance to conduct electricity.
5. Formation of Crystalline Solids
Ionic compounds form well-defined crystalline structures due to the regular arrangement of ions in a repeating pattern. These structures give them their characteristic sharp edges and flat surfaces.
6. Strong Electrostatic Forces
The forces between positive and negative ions in an ionic compound are very strong. This gives them high lattice energy, which contributes to their stability, high melting points, and hardness.
7. Exothermic Formation
The formation of ionic compounds is usually an exothermic process, meaning that energy is released when the ions come together to form a stable lattice structure. This is why ionic compounds are generally stable and exist in solid form at room temperature.
These properties make ionic compounds essential in various applications, from salts and minerals to electrolytes in batteries.
