Carbon dioxide is necessary for photosynthesis
Mission: Prove CO2 is needed for photosynthesis.
Step 1: Prep Work
We have two potted plants. We need to remove all existing starch from their leaves so we start fresh. Where do you put them?
Step 2: The Trap
We place the plants under Bell Jars. In Jar A, we want to remove all Carbon Dioxide. What chemical do we put inside?
Step 3: Secure the Perimeter
Air from the room contains CO2. How do we stop it from sneaking under the glass jar?
Step 4: Action Time
The setup is ready. Jar A has KOH (No CO2). Jar B has normal air. Where do we put the setup now?
Step 5: The Verdict
After a few hours, we test the leaves with Iodine.
What happens to the leaf from the KOH plant (No CO2)?
Experiment Successful!
The Logic:
1. The plant with KOH had no CO2.
2. It could not make starch.
3. Iodine did not turn blue-black.
Therefore, CO2 is necessary for photosynthesis!