A 500.0-mL buffer solution is 0.100 M in HNO₂ and 0.150 M in KNO₂. Determine if each addition would exceed the capacity of the buffer to neutralize it. b. 350 mg KOH

Key Concepts

Buffer Solutions

Buffer solutions are mixtures that resist changes in pH when small amounts of acid or base are added. They typically consist of a weak acid and its conjugate base or a weak base and its conjugate acid. In this case, HNO2 is the weak acid, and KNO2 provides the conjugate base, allowing the solution to maintain a stable pH despite the addition of KOH.

Buffer Capacity

Buffer capacity refers to the amount of acid or base that a buffer can neutralize before a significant change in pH occurs. It is influenced by the concentrations of the acid and base components in the buffer. The greater the concentrations, the higher the buffer capacity, meaning it can neutralize more added acid or base without exceeding its limits.

Stoichiometry of Neutralization Reactions

Stoichiometry involves the calculation of reactants and products in chemical reactions. In the context of buffer solutions, it is essential to determine how much of the buffer components will react with the added KOH. The neutralization reaction between KOH (a strong base) and HNO2 (a weak acid) will dictate whether the buffer can effectively neutralize the added base without exceeding its capacity.