Boiling water - oscillation; when oxygen needs more room

AI Thread Summary
When water is heated, oxygen molecules vibrate, leading to the formation of bubbles at the bottom of the pot, which are actually water vapor. The threshold for these bubbles to release is known as boiling, occurring when the vapor pressure equals the ambient pressure. The water remains chemically unchanged during boiling, and the bubbles consist of saturated water vapor rather than excess hydrogen. Bubbles form at specific points due to nucleation, where surface tension holds them until they grow large enough to rise. The uneven distribution of bubbles is a result of localized nucleation sites rather than uniform vapor formation.
Mallignamius
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I understand that when the oxygen molecules are heated up in a pot of water, they will vibrate increasingly as they get hotter. I guess that's what those little bubbles are at the bottom of the pot.

At some point, they will suddenly release. Is there a name for this threshold and a way to measure it? And am I correct in thinking that they are pushed up once they reach that certain point (that threshold)?

Finally, does this mean that the water is now saturated with (or has excess of) hydrogen?
 
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Mallignamius said:
I understand that when the oxygen molecules are heated up in a pot of water, they will vibrate increasingly as they get hotter. I guess that's what those little bubbles are at the bottom of the pot.
The bubbles are water vapour, not oxygen.

At some point, they will suddenly release. Is there a name for this threshold and a way to measure it? And am I correct in thinking that they are pushed up once they reach that certain point (that threshold)?
It is called boiling. It occurs when the vapour pressure of a liquid is equal to the ambient pressure.

Finally, does this mean that the water is now saturated with (or has excess of) hydrogen?
The water is not chemically altered by boiling. The bubbles release saturated water vapour. That is why a boiling kettle steams.

AM
 
If only releasing the hydrogen from water was that easy, we'd have hydrogen cars on the roads already. ;)
 
An interesting point to note however, is that when water is heated it becomes more acidic. This is due to the auto-dissociation of water (which can be attributed to the fact the water is amphoretic). Slightly off point but what the hey.:smile:
 
Okay, thanks. Much appreciated.

But I don't understand how the vapor can linger on the bottom and suddenly release or pop up. I guess that point is the threshold I am trying to figure out. Any input, or better yet, a direction to point me to study further? I don't even know if this is chemistry or physics.

I also am curious why these bubbles are isolated. Why isn't this occurrence more evenly distributed? I mean, there is area on that surface where there aren't any bubbles. As I look into the pot, there are points where the bubbles form rapidly, creating a line of released bubbles.
 
Mallignamius said:
Okay, thanks. Much appreciated.

But I don't understand how the vapor can linger on the bottom and suddenly release or pop up. I guess that point is the threshold I am trying to figure out.
The bubble of vapour is held in place by surface tension of water. Once the bubble gets large enough, its bouyancy will overcome this adhesion.

Mallignamius said:
I also am curious why these bubbles are isolated. Why isn't this occurrence more evenly distributed? I mean, there is area on that surface where there aren't any bubbles. As I look into the pot, there are points where the bubbles form rapidly, creating a line of released bubbles.
The bubbles cannot form just anywhere, they have to form at http://en.wikipedia.org/wiki/Nucleation" .
 
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