Buffer Practical Data

Drops of Acid     Water (pH)         Buffer ( PH)

0                              6.67                      10.15

1                              3.00                      10.02

2.                             2.57                       9.85

3                               2.39                      9.74

4                               2.17                      9.55

5                               2.08                      9.30

  

Note: It would have been better to have chosen a buffer with pH 7 so that it started at the same pH as water. However, this does clearly show the effectiveness of a buffer at keeping the pH relatively constant, compared to the massive change as seen when a  drop of acid is added to water

Drops of Alkali   Water (pH)         Buffer (pH)

0                                6.67                     10.15

1                               11.23                  10.31

2                               11.74                   10.46

3                               11.98                   10.66

4                               12.15                   10.76

5                               12.35                   11.06

Homework:

1. Put the data into an appropriate table

2. Plot appropraite graphs

3. Discuss the results. What does it illustrate?

4. The buffer (pH 10.01) conntained sodium hydrogen carbonate and sodium carbonate. Explain how it worked and write equations to illustrate your answer.