Final answer:
Titration of a weak acid with a strong base results in a basic solution at the equivalence point due to the presence of the weak acid's conjugate base, which makes the pH higher than 7.
Step-by-step explanation:
When titrating a weak acid with a strong base, the solution at the equivalence point is basic. This occurs because the weak acid partially dissociates in water to form H+ ions and its conjugate base. When the strong base is added, it reacts with the H+ ions to form water (OH¯ + H¹ → H₂O).
Near the equivalence point, most H+ ions have been neutralized, leading to a steep increase in pH. The remaining conjugate base of the weak acid is a weak base itself and remains in solution after all H+ ions have been neutralized, thus creating a basic solution. The pH at the equivalence is above 7, reflecting the presence of the conjugate base and indicating a basic solution.
When titrating a weak acid with a strong base, a basic solution is produced at the equivalence point due to the reaction between the weak acid and hydroxide ions (OH¯) from the strong base. This reaction leads to the formation of water and the conjugate base of the weak acid. Since the conjugate base is a stronger base than the weak acid, it increases the hydroxide ion concentration in the solution, resulting in a basic pH.