In Biology we are studying the Respiratory System.
Here is a post of Male’s blog that explains very well the topic with some tests and activities! (STUDY FROM HERE)
This is a table showing the Gaseous Exchange:
Comparing the amount of carbon dioxide in inspired and expired air we lead to a:
HYPOTHESIS: The expired air contains more carbon dioxide than the inspired air.
LIMEWATER: clear ——-CO2——-> cloudy