The solution becomes a good conductor of electricity.
Explanation
Electrical conductivity in liquids is determined by the presence of free charge carriers. In solid metals, these carriers are free electrons, whereas in liquids (electrolytes), the charge carriers are mobile ions.Distilled water is a covalent compound consisting of neutral molecules. It lacks free ions or electrons, which makes it a poor conductor of electricity. However, when common salt (Sodium Chloride, NaCl) is dissolved in distilled water, it undergoes dissociation. The salt molecules separate into positively charged sodium ions (Na+) and negatively charged chloride ions (Cl-).
These ions are free to move within the solution. When a potential difference is applied, the positive ions move toward the negative electrode (cathode) and the negative ions move toward the positive electrode (anode). This flow of ions constitutes an electric current, thereby making the salt solution a good conductor of electricity.
Key Takeaway: Pure distilled water is a poor conductor due to the absence of free charge carriers. Dissolving an electrolyte like common salt introduces free ions, significantly increasing the solution's conductivity.