Question

Select the missing words to complete the definition of buffer capacity. Buffer capacity is the _______ of acid or base a buffer can handle before pushing the _______ outside of the buffer range.

1) amount, concentration
2) concentration, amount
3) strength, concentration
4) concentration, strength

Answer 1

Buffer capacity is the amount of acid or base a buffer solution can absorb before the pH shifts significantly, and it depends on the concentrations of the buffering species.

Step-by-step explanation:

Buffer capacity is defined as the amount of acid or base a buffer can handle before pushing the pH outside of the buffer range. Therefore, the correct completion of the sentence is 'Buffer capacity is the amount of acid or base a buffer can handle before pushing the pH outside of the buffer range.' This means that buffer capacity depends directly on the concentration of the buffering species in the solution.

Buffers work by neutralizing added acids (H⁺ ions) or bases (OH⁻ ions) through reactions with the weak acid/base pair present in the buffer. Higher concentrations of the weak acid and its conjugate base allow the buffer to neutralize more added acid or base without a significant change in pH. In contrast, a buffer with low concentrations of these components would have a lower buffer capacity, changing pH more readily upon addition of acid or base.