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G-15
REPORT: EXPERIMENT G - pH TITRATION
CURVES
Name ____________________________________
Section ___________ Date ___________________
Laboratory Instructor________________________
Calculations must be shown with
the correct number of significant figures and with units.
Graph: On graph paper, complete
the titration curve for Part B and label it. The graph must be drawn
accurately, on graph paper with
a 1.0 mm grid. (0.5 marks) Show on the graph:
(a)
how to determine the pH at the equivalence
point. (0.5 marks)
(b)
the pH range where the indicator
changes color. (0.2 marks)
(c)
the pH range where values of pH
are changing most rapidly. (0.2 marks)
(d)
how to determine the pK
a
of CH3COOH
and calculate the value of K
a
. (0.6 marks)
You must clearly
indicate on the graph how to obtain these values and include a brief
explanation of the theoretical
basis for the determination of K
a
. .
1.
Write the molecular
equation for the titration reaction
of acetic acid. (0.2 marks)
2.
a)
Titrations without the pH meter:
Calculate the molarity of your
acetic acid unknown. Show all calculations
for each titration
including units and the correct
number of significant figures.
(Do not
use C1V1 = C2V2.)
(0.6 marks)
_______________run 1______________run
2
b)
Titration using the pH meter:
Calculate the molarity of your
acetic acid unknown using the information from your
pH
titration curve
of acetic acid,. Show your calculation with units and to the correct
number of
significant figures. (0.6
marks)
________________run 3
c)
Reported value for the concentration
of the unknown acid solution.
