Bubbles form in boiling water. Are these air bubbles rising (air dissolved in water) or is it water vapor forming bubbles in the liquid? If this is water vapor, I don’t understand why it is not formed in all layers of that boiling liquid, because you only see it rising from the bottom of a glass.
Asker: Hans, 31 years old
Answer
The bubbles are indeed water vapor. If it was dissolved air, the process should stop once that air is ‘used up’. However, the bubbles continue until all the water has been spoiled. The bubbles form at the bottom, because that is where it is warmest. If you add heat quickly enough, you can see bubbles forming anywhere.
Answered by
Prof Walter Lauriks
Physics Acoustics
Catholic University of Leuven
Old Market 13 3000 Leuven
https://www.kuleuven.be/
Old Market 13 3000 Leuven
https://www.kuleuven.be/
.