Photosynthesis required practical

Set up a test tube rack containing a boiling tube at a distance of 10 cm away from the light source

Fill the boiling tube with the sodium hydrogen carbonate solution

Put the piece of pondweed into the boiling tube

Leave the boiling tube for 5 minutes

Start the stopwatch and count the number of bubbles produced in one minute

Record results in the table

Repeat twice more and use data to calculate the mean

Repeat the following steps but at distances 20cm, 30cm and 40cm away from the light source