Final answer:
Adding NaOH to a buffer solution provides hydroxide ions that react with the acid component of the buffer, effectively resisting changes in pH. Beyond the buffer capacity, additional NaOH will raise the pH, potentially inhibiting enzyme activity that requires a specific pH range.
Step-by-step explanation:
Adding NaOH to a solution can cause inhibition in various chemical and biological processes. In the context of a buffer system, such as an acetic acid/sodium acetate (HC2H3O2/NaC2H3O2) buffer, the addition of NaOH provides hydroxide ions (OH-) that react with the acetic acid (HC2H3O2) present in the buffer. This reaction produces water and additional acetate ions (C2H3O2-), thus consuming the hydroxide ions without causing a significant change in pH.
However, beyond the buffer capacity, the continued addition of NaOH will eventually lead to an increase in pH as additional hydroxide ions accumulate in the solution and overwhelm the buffer system. In the case of enzyme-catalyzed reactions, adding excess NaOH can lead to a change in pH that exceeds the optimal pH range for an enzyme's activity, thus leading to inhibition of the enzyme's activity.