Chemistry Write Up

Chemistry Lab Write-Up

Title:
Paper Chromatography of Powdered Beverage Mix

Purpose/Objective:
The purpose is to be able to use liquid chromatography to separate dyes in a powdered beverage mix, calculate the Rf values for each dye, and rank the polarity of each dye present.

Hypothesis:
If we are to use the liquid chromatography to investigate the different dyes, then I think the different dyes will come up having different polarities and Rf values.

Procedure/Method:
Draw a line across the paper, 1 cm from the bottom
Use toothpick to put a drop of the beverage onto the center of the line
Repeat for the another flavor beverage on another piece of paper
Pour water into beaker
Tape each paper to a pencil and hang papers in the different beakers
Make sure paper is in water but water level is not over the drawn line
Record observations
Keep paper in until water almost reaches the top of the paper
Take them out to dry
Measure water and individual dye distances

Data and Observations:

Beverage flavor: Grape
Dyes listed on package: Red 40, Blue 1

Distance Traveled
Water
7 cm
Blue Colored Dye
1 cm
Pink Colored Dye
3.5 cm
Observations:
Split into 2 colors (pink and blue)
Blue on top and pink on the bottom

Beverage flavor: Pink Lemonade
Dyes listed on package: Red 40

Distance Traveled
Water
7.5 cm
Yellow Colored Dye
4.5 cm
Observations:
Very feint yellowish color

Data Analysis/Questions for Analysis:
1. Sample 1: seen to have red 40 and blue 1
Sample 2: supposed to have red 40, but was seen to have yellow 5
2. Rf of blue dye: 1/7 or .143
Rf of pink dye: 3.5/7 or .5
Rf of yellow dye: 4.5/7.5 or .6
3. Ranking dye (in polarity): yellow; pink; blue

Evaluation/Conclusion:
Evaluation
The experiment turned out as I expected. The different dyes also had different Rf values and polarities. Some degrees of error in the experiment could have been mislabeling the beverages, the accuracy of the measurements, or any