Photosynthesis Practical

• Photosynthesis Practical

  1. Fill beaker with water
  2. Place fresh pondweed into bottom of beaker & place funnel over top to hold in place and help collect bubbles
  3. Place beaker under high intensity light to encourage photosynthesis
  4. Fill a test tube with sodium hydrogencarbonate solution and turn upside down in beaker.
  5. When pondweed is producing steady bubble stream, place 10cm from light source
  6. Place a test tube over funnel and wait 2 minutes
  7. Start stopwatch and count bubbles for 1 minute
  8. Stop stopwatch and record results
  9. Repeat twice to calcukate mean bubbles per minutes
  10. Repeat at different distances from light source
• Photosynthesis Practical

  Sodium hydrogencarbonate solution is added to ensure there is sufficient CO2 and it is not a limiting factor
• Photosynthesis Practical

  Control Variables:

  • Flask is same distance from light source
  • Same period of time for gas production
  • Same sized piece of pondweed