Ozone Results
Creighton University
Part 5. Food coloring experiments

In this experiment, Tere measured the absorbance of Dilute Blue Food Coloring as it is being reacted with ozone (approx 800 nanomoles/min).

More Food Coloring Experiments.  We have monitored the reaction of ozone with various food colorings as a function of time.  We have concluded that ozone reacts most quickly with blue.  Here is a photo overview of the reactions with all four McCormick food colors: (Bruce's experiment)

In this initial experiment, ozone was bubbled through all four food colors (as dilute solutions) for about 5 minutes each.  When compared to the original solution, at left in each case, one can see that the solution turned colorless for each food coloring.

and, repeated more carefully...

time = 0 min

time = 1 min

time = 2 min

time = 3 min

time = 4 min

time = 5 min

time = 6 min

time = 7 min

time = 10 min

Next Tere monitored the visible spectrum of the green food coloring as a function of time: (In this experiment, ozone was bubbled through the sample cuvette for the Cary 14 spectrophotometer) (Tere page 22)

Here, are absorbance data taken at 630 nm and 427 nm for 12 minutes.  This experiment is separate from the above experiment.  Here, the ozone was bubbled through a solution of 25 mL of dilute Green Food Coloring in a 100-mL volumetric flask. (Tere page 22)