Why does an aqueous solution of an acid conduct electricity?
An aqueous solution of an acid conducts electricity because acids produce ions when dissolved in water. The electric current is carried through the acidic solution by these ions.
When an acid is dissolved in water, it dissociates to produce hydrogen ions (H⁺) as cations and corresponding anions. For example, HCl produces H⁺ and Cl⁻ ions, HNO₃ produces H⁺ and NO₃⁻ ions. The separation of H⁺ ions from acid molecules occurs only in the presence of water.
These charged particles (ions) present in the acidic solution enable the flow of electric current, making the solution conductive.
Explanation
The textbook context clearly states that 'The electric current is carried through the acidic solution by ions.' Acids contain H⁺ ions as cations and various anions (Cl⁻ in HCl, NO₃⁻ in HNO₃, SO₄²⁻ in H₂SO₄, CH₃COO⁻ in CH₃COOH). The key point is that acids produce hydrogen ions H⁺(aq) in solution, and these ions are responsible for conducting electricity. The context also emphasizes that the separation of H⁺ ions from acid molecules cannot occur in the absence of water, which is why only aqueous solutions conduct electricity.