Activity 4

• Introduce a match stick into the tube taken in the setup. It will be highly enlightened indicating that the gas in the tube is oxygen.
• Photosynthetic gas exchange is much more important than the respiratory gas exchange such that liberation of oxygen during photosynthesis is much more than the volume of oxygen consumed during cell respiration, and hence the net product is liberation of oxygen
• Sodium bicarbonate is a source of CO2


  Potassium hydroxide absorbs CO2