1. Photosynthesis – Pigments and Light Day 1
Draw the set up:
Before 72 hours Before 72 hours
of dark conditions of light exposure
What is the Bromothymol blue?
How did we turn the Bromothymol blue from blue to yellow-green?
What happened to the pH of the solution that made it turn yellow- green?
If the Bromothymol blue is yellow-green which molecule has “dissolved” into the water?
After 72 hours of dark conditions, what color do you think the bromothymol blue will be?
After 72 hours of light exposure, what color do you think the bromothymol blue will be?

2. Photosynthesis – Pigments and Light Day 2
Your Results: Please record your observation by coloring in the
test tubes the same color as the solutions.
After 72 hours After 72 hours
of dark conditions of light exposure
1. What color was the solution after 72 hours in dark conditions?
Was CO2 removed from the water by the plant? Explain.
Did photosynthesis occur?
2. What color was the solution after 72 hours in light conditions?
3. Was your hypothesis supported or refuted by these results?