The overall goal of this experiment was performed to

The overall goal of this experiment was performed to find the maximum wavelength, absorbance,
and concentration of diluted Red 40, Blue 1, and different flavors of Kool-Aid and Flavor-Aid, by
doing serial dilutions.
EXPERIMENTAL
For the first part of the experiment, the work between Red 40 and Blue 1 was split between
two groups, however, the procedures were the same for both parts. In Part A of this experiment, two
students prepared a 2-fold serial dilution of the “Red 40” stock solution by diluting 5mL of each
2

previous solution with 5mL of deionized water. The 5mL volumetric pipette and pipette pump were
assembled and the concentration (50.2ppm) of the “Red 40” stock solution was recorded. The 5mL
volumetric pipette was used to add 5mL of the “Red 40” stock solution to a clean 10mL volumetric
flask labeled “R1.” The volumetric flask was filled to the line with deionized water in order to
achieve a total volume of 10mL, and then the flask was capped and inverted several times to ensure
the solution was mixed properly. The volumetric pipette was then rinsed with fresh deionized water
and then 5mL of the “R1” solution was added to a clean 10mL volumetric flask labeled “R2.” The
volumetric flask was filled to the line with deionized water in order to achieve a total volume of
10mL, and then the flask was capped and inverted several times to ensure the solution was mixed
properly. The volumetric pipette was then rinsed with fresh deionized water and then 5mL of the
“R2” solution was added to a clean 10mL volumetric flask labeled “R3.” The volumetric flask was
filled to the line with deionized water in order to achieve a total volume of 10mL, and then the flask
was capped and inverted several times to ensure the solution was mixed properly. The volumetric
pipette was then rinsed with fresh deionized water and then 5mL of the “R3” solution was added to
a clean 10mL volumetric flask labeled “R4.” The volumetric flask was filled to the line with
deionized water in order to achieve a total volume of 10mL, and then the flask was capped and
inverted several times to ensure the solution was mixed properly. The volumetric pipette and the
pipette pump were cleaned with deionized water, and the concentrations of each solution were
calculated using the equation C
1
V
1
=C
2
V
2
and recorded in Table 1 below.
Table 1: Volumes and Concentrations for Serial Dilution of Red 40
Initial
Concentration
Initial Volume Total Volume New
Concentration
Flask
50.2 ppm 5 mL 10 mL 25.1 ppm R1
25.1 ppm 5 mL 10 mL 12.55 ppm R2
12.55 ppm 5 mL 10 mL 6.275 ppm R3
6.275 ppm 5 mL 10 mL 3.1375 ppm R4
For second half of Part A of this experiment, two students prepared a 2-fold serial dilution of
the “Blue 1” stock solution by diluting 5 mL of each previous solution with 5 mL of deionized water.
3

The 5mL volumetric pipette and pipette pump were assembled and the concentration (16.1ppm) of
the “Blue 1” stock solution was recorded. The 5mL volumetric pipette was used to add 5mL of the
“Blue 1” stock solution to a clean 10mL volumetric flask labeled “B1.” The volumetric flask was filled