Using eq. 7: BC = 2.3 / (1/WA) + (1/CB)

calculate the buffer capacity (BC) of your buffer solution before and after dilution with water, and enter the values obtained below. Remember that before dilution the water volume in the flask was 25 mL. After dilution, the volume was 35 mL. The number of moles of weak acid and conjugate base will depend on the amounts added to the flask. Your weak acid's molar mass is 234 and that of the conjugate base is 256.

Data:

pH of Pure Water

7

pH of Water + NaOH

11.58

WA Mass

0.2215

WA pH

3.34

WA + Water pH

3.42

WA+ NaOH pH

4.34

Conj Base Mass

0.2014

Conj Base pH

8.85

CB + Water pH

8.78

CB + NaOH pH

11.45

Mass of WA for Buffer Solution

0.1892

Mass of CB for Buffer Solution

0.1998

Buffer pH

5.18

Buffer + Water pH

5.18

Buffer + NaOH pH

5.28

pH after Adding NaOH to Water

4.58

pH after Adding NaOH to Diluted WA

0.92

pH after Adding NaOH to Diluted CB

2.67

pH after Adding NaOH to Diluted Buffer

0.1

Water Rank

4

Weak Acid Rank

2

Conj Base Rank

3

Buffer Rank

1

Buffer Base

1

Buffer H₃0+

5

Weak Acid pK_a

4.6

pH for Buffer Solution

4.56