Moist Air Convection Myth

[webolife]

I have another challenge for you: several years ago some science teacher colleagues and I did a "mythbusters" style experiment freezing different temperatures of water under the same conditions, in ice cube trays in a normal household freezer. The claim we addressed was the legendary claim that "hot water freezes faster than cold water." The trays were placed into the freezer at the same time. Quite to our surprise, and for reasons yet uncertain [although I'm sure you and I have some conjectures], several trials of this experiment showed that the "hot water" trays began to skin over with ice at around 3deg C, several minutes before the cold water trays begin to do this at a degree or two colder. At the conclusion, we found that the cold water trays froze completely before the hot water trays froze.

Also, Pollack's work has shown that at the critical freezing point of water, an infrared burst is detected.

What do you think?

[kevin]

As for water altering in density above and below 4c....
Consider about pressure.
http://chemguide.co.uk/physical/phaseeq ... diags.html
Kevin

[jimmcginn]

I have another challenge for you: several years ago some science teacher colleagues and I did a "mythbusters" style experiment freezing different temperatures of water under the same conditions, in ice cube trays in a normal household freezer. The claim we addressed was the legendary claim that "hot water freezes faster than cold water."

Mpemba effect. Rediscovered by an African culinary student.

The trays were placed into the freezer at the same time. Quite to our surprise, and for reasons yet uncertain [although I'm sure you and I have some conjectures], several trials of this experiment showed that the "hot water" trays began to skin over with ice at around 3deg C,

Thus indicating--at least in part--that more 'flipping' had been achieved, I'm guessing.

several minutes before the cold water trays begin to do this at a degree or two colder. At the conclusion, we found that the cold water trays froze completely before the hot water trays froze.

Those results are very interesting. I think the effect would show up more dramatically if you had had something mixed in with the water. Part of the reason I say this is, well, very complicated (it relates to non-Newtonian fluids). But the other part is not: Mpemba was making ice cream/custard when he rediscovered this.

This is confusing problem because in order to get the right answer you have to understand 1) H2O high heat capacity 2) H2O surface tension; and 3) on top of all that you have to have a basic understanding of thermodynamics. The paper/chapter I'm about to release will, I believe, explicate my thinking on 1 and 2. And, actually, the topic of the second Chapter is the relationship of H2O to energy. (Like you I'm mostly an earth sciences guy, so I am a bit out of my element with thermodynamics.)

I don't have a concise explanation for Mpemba yet. Or, I should say, I don't have one that doesn't require me to first explain to you my thinking on 1) and 2) above. Even then I'm not sure, but here are some factors to consider (warning, some of this is going to sound weird):

1) As is well known, liquid H2O has a high heat capacity. As is also well known, liquid H2O has high heat conductivity. However, what is not as well known (or simply not considered) is that liquid H2O DOES NOT have the ability to conduct heat (energy) over distance. (Think about that for a second.) And so, even though H2O has a high heat conductivity this tends to be local.

2) Ice has a low heat capacity. It has a high heat conductivity. And, most significantly, it has a very high ability to conduct energy over distance!

3) Now here is the weird part: There is more ice in warm, agitated (liquid) water than there is in cool calm (liquid) water.

You can't possibly know what I mean by #3 until after you've read and comprehended my first chapter.

Also, Pollack's work has shown that at the critical freezing point of water an infrared burst is detected.

Wow! I suspect I might have come across this before in Pollacks writing but until you mentioned it here its significance never occurred to me. I'm not sure but I think my model actually predicts this. Enough said for now, but it relates to stopping the thermal heartbeat associated with H2O's high heat capacity. Thank you for bringing this to my attention.

James McGinn / Solving Tornadoes

[Maol]

I have another challenge for you: several years ago some science teacher colleagues and I did a "mythbusters" style experiment freezing different temperatures of water under the same conditions, in ice cube trays in a normal household freezer. The claim we addressed was the legendary claim that "hot water freezes faster than cold water." The trays were placed into the freezer at the same time. Quite to our surprise, and for reasons yet uncertain [although I'm sure you and I have some conjectures], several trials of this experiment showed that the "hot water" trays began to skin over with ice at around 3deg C, several minutes before the cold water trays begin to do this at a degree or two colder. At the conclusion, we found that the cold water trays froze completely before the hot water trays froze.

Also, Pollack's work has shown that at the critical freezing point of water, an infrared burst is detected.

What do you think?

It sheds latent heat when it changes state from liquid to solid. The specific enthalpy of fusion (AKA latent heat) of water is 333.55 kJ/kg at 0 °C. It emits or absorbs that heat when it changes state, one way or the other.

[webolife]

The infrared burst discovery is something one of Pollack's assistants was working on when I visited his lab at the
UW. I actually don't remember seeing that result in published form.

[GaryN]

Does this finding change anything in the models being discussed here?

Physicists just discovered a second state of liquid water

Researchers have been investigating the physical properties of water, and found that when it’s heated to between 40 and 60 degrees Celsius, it hits a 'crossover temperature', and appears to start switching between two different states of liquid.

http://www.sciencealert.com/physicists- ... quid-water

[Maol]

Ultrasonic cleaners work better, clean faster, when the water is near and above about 60*C. Literature about using the cleaners describes the effect of water temperature on the characteristics of ultrasonic cavitation.

[webolife]

It sheds latent heat when it changes state from liquid to solid. The specific enthalpy of fusion (AKA latent heat) of water is 333.55 kJ/kg at 0 °C. It emits or absorbs that heat when it changes state, one way or the other.

In "my" Centropic Pressure Field theory, I don't view heat as being "shed" per se. Rather as the freezing H2O configuration stabilizes, it reduces its effective energy level [increases entropy]. This is the purported cause of heat in a variety of applications. The twist is that the "heat vector" is toward the system locus [centropic], rather than away from it. The detector may or may not have inherent capability to discern the direction of the vector, that must be supplied by theory. To help visualize this more concretely, simply imagine what requirement is needed to increase the experience of heat... moving toward the "source", or away from it?

And Gary, that just adds yet one more state for our "everyday" water!! Dr. Pollack already describes the 4th phase of water as the gel stage found along electrically polarized EZ interfaces... Now two stages of warm water?!

Jim, you may have to rewrite your book before it's finished the first time!

[GaryN]

webolife:

And Gary, that just adds yet one more state for our "everyday" water!!

I have only just begun looking into water in any detail, and the complexity of such a common (to us in the Pacific N.W.!) substance has already amazed me. I have been looking into the spectral properties, and found this page:
Water Absorption Spectrum
http://www1.lsbu.ac.uk/water/water_vibr ... ctrum.html
I was looking for emission lines really, in the LWIR, but I'll try to 'absorb' the info on that page first.

[webolife]

Gary,
That is a real gem of a paper. Thanks for sharing!

[seasmith]

A
Question for Webolife, or anyone who has a fair comprehension of most of the stuff discussed in that paper:

What influence if any, does the frequency band of the irradiating source used (for all varieties of spectroscopy) have on the produced (re-) emission and absorption lines of a probed water molecule ?

Obviously the spectrum band width of the Excitation Source will generally ~limit the width of the response spectrum, but my question specifically is:
will a tested sample exhibit different Emission Spectrum and Lines, dependent on the irradiating radiation;
e.g. coherent laser, intense white, LWIR, SWIR, microwave, UUV, etc. ?
?

[webolife]

A few things to keep in mind:
1. Water is primarily an absorber not a reflector of light. If you are at a low angle of course you see great reflections, but that is true of lots of different surfaces. As far as I know, H2O does not have much of an emission spectrum. If it did it would be a lot easier to detect water on other planets, moons, and stellar systems. Astronomers searching for water must rely on inferences from other ions, eg. hydroxyl. What the paper deals with is mostly absorption properties.
2. Water is a good absorber of the red/IR part of the spectrum, which is why it looks blue.
3. Different water densities, as was brought up a few posts back, have different absorptive properties. Once you have these concepts in hand, the paper will be more informative for you.

[seasmith]

Webo,
Was that an answer to my question ?

Yes, water is primarily an 'absorber', but there is always some transmittance/re-emission/reflection, (like with microscopy) depending on how a sample is probed, and where the detector is positioned.
If it was all absorption, there would be no bright lines, and hence no spectrum to analyze, yes?

[seasmith]

To restate the question more simply;
Wouldn't the resultant emission spectrum differ, depending on the 'radient energy' of a source
on that wide scale from microwave to gamma wave and beyond?
Or do we know ?

[webolife]

Seasmith,
I think I may have misunderstood your question... the spectrum we see is the result of and identifies the light source/sink... to see an emission spectrum of water, you have to essentially burn it so that it becomes the light source, or part of it, as in for example an acetylene torch flame. Or, correcting a previous statement of mine, a stellar atmosphere. Not too far past, it was not possible to identify water in a stellar atmosphere, but more intensive studies with better equipment are apparently allowing this, for example in studying red giant stars.
If on the other hand, you are picturing shining a certain light frequency through water, what you will get is the water's absorption spectrum. Because the light frequency is already "filtered" in that scenario, you will only get whatever response the water has to that frequency... Shining an IR light through water will yield water's absorbancy profile for that range of frequencies, whereas shining a broad spectrum [eg. white] light through it will yield a broader range of the water spectrum profile.
Essentially, the average configuration of electrons in a group of atoms or molecules characterizes that particular element or compound, ie. makes it react the way it does; this same configuration also resonates with particular frequencies of light, reflecting those frequencies [I would say pressure "angles"] or not [in the case of absorption] to the detector, eg. your eye.
Also, it is not a single molecule or atom that provides a spectrum, at least one we can analyze, rather a "bundle" of them. In the case of water as is being explained in that paper, various rotations of the water molecules, or temperature induced bond stretching and bending, yield different absorptive results, which show up in the spectral analysis.