Sodium Chloride (NaCl):
* Ionic Compound: Sodium chloride is an ionic compound. This means it's formed by the electrostatic attraction between positively charged sodium ions (Na+) and negatively charged chloride ions (Cl-).
* Dissociation in Water: When sodium chloride dissolves in water, the ionic bonds break, and the ions become surrounded by water molecules. These ions are now free to move independently within the solution.
* Conductivity: The presence of free, mobile ions allows the solution to conduct electricity. When an electrical potential is applied, the positively charged ions move towards the negative electrode (cathode), and the negatively charged ions move towards the positive electrode (anode). This flow of charge constitutes an electric current.
Sugar (Sucrose):
* Covalent Compound: Sugar is a covalent compound. Its atoms are held together by shared electrons, forming strong, neutral molecules.
* No Free Ions: When sugar dissolves in water, it does not break down into ions. The sugar molecules remain intact and do not carry electrical charge.
* No Conductivity: Since there are no free ions to carry the charge, a sugar solution does not conduct electricity.
In Summary:
The ability of a solution to conduct electricity depends on the presence of free, mobile ions. Ionic compounds like sodium chloride dissociate into ions in solution, allowing for conductivity. Covalent compounds like sugar do not form ions in solution and therefore do not conduct electricity.
