Activity to show the uptake of oxygen during aerobic respiration
Answers
Answer:
Investigating respiration
Respiration by living organisms can be investigated by carrying out experiments to show the production of carbon dioxide and heat.
Investigating carbon dioxide production
Limewater turns milky in the presence of carbon dioxide. It can be used to show that exhaled air contains more carbon dioxide than inhaled air.
Carbon dioxide dissolves in water to form a weakly acidic solution. Hydrogencarbonate indicator is used to show the presence of carbon dioxide in solution. It is:
-red at neutral pH (no carbon dioxide)
-yellow at low pH (carbon dioxide present)
Air travels to pump via four conical flasks.
1: sodium hydroxide solution absorbs carbon dioxide.
2: indicator solution, turns red.
3: respiring organisms.
4: indicator turns yellow.
To pump.
In this experiment, the sodium hydroxide solution in the left-hand flask absorbs carbon dioxide, so the respiring organisms must have produced the carbon dioxide detected in the right-hand flask.