Plan two investigations to show that plants use carbon dioxide and release oxygen during photosynthesis, in clue what materials to will need, what data you will collect and what procedures to follow?

Answer 1

Investigation 1: Testing the production of oxygen during photosynthesis

Materials needed:
- Water
- Aquatic plants such as Elodea
- Light source
- Test tube
- Test tube holder
- Water-filled beaker
- Stopwatch
- Sodium bicarbonate (to increase the supply of carbon dioxide)

Procedure:
1. Fill a test tube with water and place a small piece of Elodea plant inside it.
2. Fill a larger beaker with water and cover the test tube with it, ensuring no air bubbles are trapped inside.
3. Place the setup under a light source and allow the plant to photosynthesize for a few hours.
4. Use sodium bicarbonate to increase the supply of carbon dioxide to the plant.
5. Use a stopwatch to measure the time it takes for bubbles to form in the test tube and rise to the top (this indicates the production of oxygen).

Data collected:
- Time taken for bubbles to form and rise in the test tube.

Investigation 2: Testing the use of carbon dioxide during photosynthesis

Materials needed:
- Potted plant
- Plastic bag
- Rubber band
- Sodium bicarbonate
- Light source
- pH indicator solution

Procedure:
1. Place a potted plant inside a plastic bag and seal the opening with a rubber band.
2. Add a small amount of sodium bicarbonate to the bag to increase the supply of carbon dioxide.
3. Leave the setup under a light source for a few hours to allow the plant to photosynthesize.
4. Remove the plant from the bag and test the pH of the remaining solution inside the bag using a pH indicator solution.
5. Compare the pH of the solution before and after the experiment (a decrease in pH indicates the plant has used carbon dioxide).

Data collected:
- pH of the solution inside the plastic bag before and after the experiment.