You are provided with two vials, each containing a different flavor of Kool-Aid® drink mix dissolved — Chromatography Chemistry Question
Problem Context
You are provided with two vials, each containing a different flavor of Kool-Aid® drink mix dissolved in water. Devise and carry out a procedure to rank the polarity of the artificial coloring found in both samples.
Give a brief description of your experimental plan.
Model Answer
• Indication that paper chromatography will be used to solve the problem
• Excellent plan would indicate trying different eluents (isopropanol, water, and mixtures of isopropanol and water)
• Students should provide details about set-up – a sketch is an excellent way to provide information about the set-up, indicate start and end point, spot above solvent line
Record your data and other observations.
Model Answer
• Qualitative observations: numbers of spots and colors of the spots, degree of migration in the eluent
• Quantitative observations: providing Rf or a sketch to scale demonstrating the migration distance
How many dyes are present in each sample? Specify the number and color(s) of the dye(s) in each sample.
Kool-Aid 1 flavor: _____________________________________(record information from label of vial)
Kool-Aid 1 number of dye(s) and colors of the dye(s) in the sample: _______________________________
_______________________________________________ _______________________________________
Kool-Aid 2 flavor: _____________________________________(record information from label of vial)
Kool-Aid 2 number of dye(s) and colors of the dye(s) in the sample: _______________________________
_______________________________________________ _______________________________________
Model Answer
Answer depends on the Kool-Aid samples provided to the student.
The ingredients on the packages of Kool-Aid are as follows:
Green Apple: Yellow 5 and Blue 1
Grape: Red 40 and Blue 1
Orange: Red 40 and Yellow 5
Does/Do the same dye(s) exist(s) in more than one sample(s) of Kool-Aid? If yes, please specify which dye(s) and the sample that contain the same dye(s).
Model Answer
Answer depends on the Kool-Aid samples provided to the student.
The ingredients on the packages of Kool-Aid are as follows:
Green Apple: Yellow 5 and Blue 1
Grape: Red 40 and Blue 1
Orange: Red 40 and Yellow 5
Rank the dyes in order of increasing polarity
Least polar Most polar
Model Answer
least polar most polar
water as eluent: blue yellow red
isopropanol as eluent: blue red yellow