1. BW- Paper Lab Without carbon dioxide: indicator is blue;
BACKGROUND: In water, carbon dioxide dissolves to form a weak acid.
As a result, an acid-based indicator such as bromothymol blue can be used to indicate the presence of carbon dioxide.
Without carbon dioxide: indicator is blue;
With carbon dioxide: indicator is yellow-green.
In this investigation, we will use bromothymol blue to investigate whether photosynthesis is occurring & then explain how we know.

2. DAY 2: tube under light: in dark:
DAY 1 with Elodea plant in Bromothymol blue solution & CO2- there are 2 tubes that look like this
Put 1 tube on a light cart & put 1 tube in a drawer (dark)
DAY 2: tube under light: in dark:

3. DAY 2: tube under light: in dark:
BW Questions:
What is the IDV?
What is the DV?
In what photosynthetic reaction is CO2 used?
What is needed for CO2 to be used
How are these reactants (from Q#4) produced?
What specifically caused the tube to change from yellow-green to blue?