Photosynthesis

We were answering the question "How can we prove plants use carbon dioxide for photosynthesis" We used a plant called Cabomba put it into clear containers with hydrocarbonate indicator. One plant we put in the dark, one in the light and we had a control with no plant.

Hydrocarbonate turns from red to purple if carbon dioxide is decreasing and turns yellow if carbon dioxide is increasing. (Robbie's answer)

Here are our results. The one in the light turned purple because the plant was using up the CO2 for photosynthesis faster than it was producing it by respiration. (Andrews answer)

The one in the dark turned yellow because no photosynthesis was happening in the dark and the plant was respiring so producing CO2 (Kerr' s answer)

The control stayed the same showing that the changes were taking place because of the plant.

Here are our pictures showing our results - sorry they are a bit blurry!

Posted by S2 boys (as all the girls were absent today)