Question

In the experiment to show that ‘CO₂ is released during respiration’_, vaseline is used to

• A. make the experimental set up shine
• B. make the experimental set up air tight
• C. clean the experimental set up
• D. allow CO₂ to be released slowly

Answer 1

The correct option is B

make the experimental set up air tight

The correct option is B.

Explanation of the correct option:

• Germinating seeds follow the aerobic mode of respiration.
• During aerobic respiration, carbon dioxide is released.
• The release of carbon dioxide cannot be analyzed if vaseline is not used to seal the neck of the conical flask.
• Without vaseline, carbon dioxide would leak out from the flask and hence can't be absorbed by potassium hydroxide solution.

Explanation of the incorrect options:

Option A:

• Shining the experimental setup is not a related thing to laboratory experiments.

Option C:

• Experimental setup can be kept clean by following proper procedures. Vaseline does not clean the experimental setup.

Option D:

• Carbon dioxide is released by plants during the process of photosynthesis via stomata. Vaseline does not cause the release of carbon dioxide.

Therefore, the vaseline is used to make the experimental setup airtight for demonstrating the carbon dioxide released during respiration.