How do magnets affect boiling water?

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    Boiling Water
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Discussion Overview

The discussion revolves around the effects of magnets on boiling water, particularly focusing on the behavior of bubbles during the boiling process. Participants explore the mechanisms behind bubble formation and the potential influence of magnets on this phenomenon.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant observes that bubbles in boiling water start large and then shrink as they rise, questioning the underlying causes of this behavior.
  • Another participant explains that the bubbles are water vapor formed when the temperature exceeds the boiling point, but the surrounding water remains below this temperature, leading to the bubbles shrinking as they ascend.
  • A participant questions whether the gas in the bubbles is simply water vapor or a breakdown of water into hydrogen and oxygen, and suggests that the presence of magnets may influence bubble formation by providing additional nucleation sites.
  • Another participant proposes that the magnets may attract dust or particles that could serve as nucleation sites, and notes that the surface texture of the magnets might differ from that of the pot, potentially affecting bubble formation.

Areas of Agreement / Disagreement

Participants express differing views on the role of magnets in bubble formation, with some suggesting that they enhance nucleation while others focus on the thermal properties and surface characteristics of the magnets. The discussion remains unresolved regarding the exact influence of magnets on boiling water.

Contextual Notes

There are uncertainties regarding the thermal properties of standard magnets and how they interact with boiling water, as well as the specific mechanisms of bubble formation in relation to surface irregularities and nucleation sites.

jammieg
Have you ever watched a pot of water boil? I'll bet you have, but did you notice how the bubbles start off at the bottom in just a few spots as if there were an air leak from the bottom of the pot and they start off really big and then almost instantly reduce in size so small sometimes you can't even see them before floating to the top, isn't that odd? What's going on here, what would cause a bubble to do that, this is no ordinary bubble.
 
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The bubble is just water in the gas phase. At the point it is formed, the temperature exceeds the boiling point. But the liquid water above it is still below the boiling point. So as soon as it starts to rise, it shrinks and winks out.
 
When you say it is water in the gas phase, do you mean it is oxygen and hydrogen gas broken down or just water vaporized to a gaseous form and that it is actually the ascension of the bubble that rapidly cools and this is what accounts for the rapid size shift? The reason I ask is when i put some magnets in the bottom of the pot a curious thing happened I can't explain but all the bubbles formed around the magnets, if the hottest areas give rise to the gaseous bubbles, it would seem that additional magnets would just give greater surface area and be cooler regions of the pot, I don't know about the thermal properties of standard magnets though, odd though isn't it?
 
jammieg said:
The reason I ask is when i put some magnets in the bottom of the pot a curious thing happened I can't explain but all the bubbles formed around the magnets, if the hottest areas give rise to the gaseous bubbles, it would seem that additional magnets would just give greater surface area and be cooler regions of the pot, I don't know about the thermal properties of standard magnets though, odd though isn't it?

I think the bubbles start at irregularities in the surface of the pot, like scratches or sharp little protuberances. The magnets are likely to hold a lot of dust or other particles that can serve as nucleation sites for the bubbles. Also the magnets may be made of a material that has a coarser surface texture than the pot.
 

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