1. Dissolving: When an ionic compound like sodium chloride (NaCl) dissolves in water, the strong electrostatic attraction between the positive sodium ions (Na+) and negative chloride ions (Cl-) is overcome by the polar water molecules.
2. Dissociation: The water molecules surround and separate the ions, effectively breaking the ionic bond and forming individual, mobile ions in solution.
3. Conductivity: These free ions can move independently within the solution. When an electric potential is applied across the solution, the positive ions move towards the negative electrode (cathode) and the negative ions move towards the positive electrode (anode). This flow of charged particles constitutes an electric current.
Key points:
* Free ions are essential: The ability of ionic compounds to conduct electricity in solution relies on the presence of free, mobile ions.
* Solid ionic compounds don't conduct: In their solid state, the ions are fixed in a crystalline lattice and cannot move freely.
* Electrolytes: Solutions containing ionic compounds that conduct electricity are called electrolytes.
In summary, the ability of ionic compounds to conduct electricity in solution is due to the formation of free, mobile ions when they dissociate. These ions can then carry an electric current under the influence of an electric field.
