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. c. 1.25 g HBr

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, the buffer is composed of HNO2 (a weak acid) and KNO2 (its conjugate base), which helps maintain the pH when HBr, a strong acid, is introduced.

Buffer Capacity

Buffer capacity refers to the amount of acid or base that a buffer solution can neutralize before a significant change in pH occurs. It depends on the concentrations of the weak acid and its conjugate base. In this scenario, the buffer's capacity will be tested by the addition of HBr, and determining whether the buffer can handle this addition is crucial for understanding its effectiveness.

Stoichiometry of Acid-Base Reactions

Stoichiometry involves the calculation of reactants and products in chemical reactions. For the buffer solution, the addition of HBr will react with the weak base (KNO2) present in the buffer. Calculating the moles of HBr added and comparing it to the moles of KNO2 will help determine if the buffer can neutralize the added strong acid without exceeding its capacity.