1. Blue and Gold Demonstration

2. Addition of Solution X Continued Stirring in Air What questions do you have? Addition of Solution X Continued Stirring in Air

3. Blue and Gold Demonstration Addition of Na 2 S 2 O 4 a reducing agent Continued Stirring in O 2 Oxidized Indigo Carmine Reduced Indigo Carmine

4. Blue and Gold Demonstration Addition of Na 2 S 2 O 4 a reducing agent Continued Stirring in O 2 Oxidized Indigo Carmine Reduced Indigo Carmine

5. Blue and Gold Demonstration Addition of Na 2 S 2 O 4 a reducing agent Continued Stirring in O 2 Oxidized Riboflavin Reduced Riboflavin

6. Blue and Gold Demonstration Addition of Na 2 S 2 O 4 a reducing agent Continued Stirring in O 2 Oxidized Fiboflavin Reduced Riboflavin

7. Blue and Gold Demonstration Oxidized riboflavin fluorescence when irradiated with ultraviolet light

8. Successive addition of dithionite Color ABCD Continued stirring exposed to air ? Blue and Gold Demonstration The dark line on figure to the left depicts the change in color intensity as a function of added dithionite for both indigo and riboflavin. What is happening chemically in regions labeled A, B, C, and D? Why doesnt the color change as shown in the diagonal dashed line?