Margaret BarbeeEllie OkweiCHEM 1252L-045April 21, 2016Lab 10Purpose:The purpose of this lab is to determine the pKa by finding the half neutralizationpoint of a solution. A lower pKa value will correspond to a stronger acid. The pKacan be found by taking the –log (Ka), where Ka is the standard of acidity.For example, the solutions resulting from the naturalization of half the acid will haveequal
...[Show More]
Margaret Barbee
Ellie Okwei
CHEM 1252L-045
April 21, 2016
Lab 10
Purpose:
The purpose of this lab is to determine the pKa by finding the half neutralization
point of a solution. A lower pKa value will correspond to a stronger acid. The pKa
can be found by taking the –log (Ka), where Ka is the standard of acidity.
For example, the solutions resulting from the naturalization of half the acid will have
equal concentrations of CH3COO- and CH3COOH (a weak acid and its conjugate
base). The Henderson-Hassel Balch equation is used when there is a mixture of an
acid and its conjugate base. When the concentration of CH3COOH is equal to the
concentration of CH3COO-, then pH=pKa.
The half naturalization method involves testing a small sample of the solution with a
universal indicator, after each addition of a base. When the solution becomes blue,
then the neutralization point has been reached, and the experimenter checks for
when one-half of the volume of NaOH required for naturalization. If the pH is
monitored by using a pH meter, then a titration curve can be generated and used to
locate the equivalency point, and also determine the half equivalence point.
Procedure:
Part 1:
https://www.coursehero.com/file/35093167/Lab-10docx/
This study resource was
s
[Show Less]
-preview.png)
-preview.png)
