Question

Acetic acid has a pKa of 4.74. Buffer A: 0.10 M HC2H3O2, 0.10 M NaC2H3O2 Buffer B: 0.30 M HC2H3O2, 0.30 M NaC2H3O2 Buffer C: 0.50 M HC2H3O2, 0.10 M NaC2H3O2 Which of the above buffers has the highest buffer capacity? [ Select ] Which of the above buffers has the lowest buffer capacity? [ Select ]

Answer 1

From the data provided;

• Buffer B has the highest buffer capacity
• Buffer C has the lowest buffer capacity

What is a buffer?

A buffer is a solution which resists changes to its pH when a small quantity of acid or base is added to it.

The buffer capacity is determined using the Henderson-Hasselbach equation:

• pH = pKa + log ([CH3COO-]/[CH3COOH])

For Buffer A: pH = 4.74 + log(0.10/010) = 4.74

Buffer B: pH = 4.74 + log(0.30/030) = 4.74

For Buffer C: pH = 4.74 + log (0.10/0.50) = 4.04

Buffer A and Buffer B has same pH value as the pKa of acetic acid.

However, Buffer B has higher concentration of the components compared to buffer A, therefore, Buffer B has the highest buffer capacity.

The pH of buffer C is lower than pKa of acetic acid. Hence, buffer C has the lowest buffer capacity.

Learn more about buffers at: https://brainly.com/question/22390063