A titration curve of strong acid and strong base shows the gradual change in pH as one solution is added to another, helping us understand acid-base reactions.
The curve begins when a strong base like sodium hydroxide (NaOH) is slowly added to a strong acid like hydrochloric acid (HCl). At first, the pH stays very low around 1-3 as the acid is still in excess. As more base is added, the pH starts to rise gradually. When we reach the equivalence point - where the moles of acid exactly equal the moles of base - there's a dramatic jump in pH. This sharp vertical rise is characteristic of strong acid-strong base titrations, with the equivalence point occurring at pH 7.
When we investigate pH changes in acid-base titrations, we see different patterns depending on the strength of the acid and base used. The effect of weak acid strong base titration on pH produces a curve that's more gradual compared to strong acid-strong base titrations. With weak acids, we see a buffer region where the pH changes very slowly despite adding more base. This happens because weak acids only partially dissociate in water, creating a mixture of acid and its conjugate base that resists pH changes. The equivalence point also occurs at a pH above 7, typically around 8-10, because the salt formed from a weak acid and strong base undergoes hydrolysis. Understanding these differences helps chemists choose appropriate indicators and determine unknown concentrations accurately. The shape and features of titration curves provide valuable information about the strength of acids and bases, their concentrations, and the progress of neutralization reactions.
