Question

Explain the activity to show that co2 is released during respiration

Answer 1

Take in a beaker lime water 5 g

Then blow air on it through pipe then lime water turns milky then it means that CO2 realease during respiration

Overall equ

CaO +CO2 =CaCO3

Answer 2

Aim :-

To show experimentally that CO₂ is released during the process of respiration .

Materials required :-

• U - shaped delivery tube
• Soaked gram seeds
• conical flask
• blotting paper / cotton wool
• thread
• water
• beaker
• test tube
• rubber cork with a single hole
• Freshly prepared KOH soln. 20%
• Vaseline

Procedure :-

• Germinate close to 25 seeds . This can be done by wrapping them in moist blotting paper or cotton wool for around 3 to 4 days
• Set up the sprouted seeds in conical flask . Soray some water into the flask to dampen the seeds .
• With the help of a thread , suspend the conical flask containing the test tube having a freshly prepared 20% KOH soln.
• Use the runner cork to seal the opening of the conical flask .
• One edge of the U - shaped glass delivery tube present in the conical flask should be inserted through the hole in the rubber cork . The other end should be placed into a beaker that is saturated with water .
• All attachments of the first set up should be sealed . This can be done using Vaseline to create air tight environment .
• The initial water level present in the U - shaped delivery tube needs to be marked .
• Leave the experimental set up for 1-2 hours .

Observation :-

Careful observation after a certain period of time reveals that the water level in the U - shaped delivery tube has risen in the beaker .

Conclusion :-

The rise in the water level indicates that CO₂ is released as a result of germinating gram seeds during the process of respiration in the conical flask . The CO₂ that is released in the process is absorbed or consumed by the KOH soln. that is suspended in the test tube in conical flask , creating a vacuum or a void in the flask resulting in the upward water movement in the tube . Hence , the water level in the tube changes .

Precautions :-

• The seeds that are germinated needs to be moistened .
• Air tight environment for all the connections in the experimental set up .
• The KOH soln. that is used needs to be freshly prepared .
• Care needs to be taken to ensure that one end of the delivery tube is placed in the conical flask . The other edge is submerged in the water of the beaker .
• The tube that contains the KOH soln. needs to be suspended carefully .