Water As An Element of Fine-Tuning

and the worst part is that I "corrected" it -- should a stuck with the first (like they tell you to do when taking tests...)

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we are limited in our ability to understand
by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

Heh, I noticed that, too. I'm just too nice to say.But since holmes got to make fun of you...Har har! *points and laughs*

One other misconception of RustyShackelford that should be corrected is that water is a "universal solvent." It's a good solvent but not universal.As my chemistry prof once carefully explained it to our class, water is a universal solvent...of stuff that dissolves in water. Notably, large nonpolar/hydrophobic compounds are *not* very water soluble (they will have solubility constants of, say, 10^-49 or whatever, so that in a swimming pool full of water you will dissolve less than one molecule. This is good, because otherwise our bodies would dissolve into goo.Sulfides are also very, very resistant to dissolving in water, which is why you can remove dissolved toxic ions from solution by adding sulfide.See this Solubility product table

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Actetates
AgC2H3O2 -- 2 x 10-3

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Bromides
AgBr -- 5 x 10-13
PbBr2 -- 5 x 10-6

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Carbonates
BaCO3 -- 2 x 10-9
CaCO3 -- 5 x 10-9
MgCO3 -- 2 x 10-8

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Chlorides
AgCl -- 1.6 x 10-10
Hg2Cl2 -- 1 x 10-18
PbCl2 -- 1.7 x 10-5

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Chromates
Ag2CrO4 -- 2 x 10-12
BaCrO4 -- 2 x 10-10
PbCrO4 -- 1 x 10-16
SrCrO4 -- 4 x 10-5

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Fluorides
BaF2 -- 2 x 10-6
CaF2 -- 2 x 10-10
PbF2 -- 4 x 10-8

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Hydroxides
Al(OH)3 -- 5 x 10-33
Cr(OH)3 -- 4 x 10-38
Fe(OH)2 -- 1 x 10-15
Fe(OH)3 -- 5 x 10-38
Mg(OH)2 -- 1 x 10-11
Zn(OH)2 -- 5 x 10-17

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Iodides
AgI -- 1 x 10-16
PbI2 -- 1 x 10-8

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Sulfates
BaSO4 -- 1.4 x 10-9
CaSO4 -- 3 x 10-5
PbSO4 -- 1 x 10-8

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Sulfides
Ag2S -- 1 x 10-49
CdS -- 1 x 10-26
CoS -- 1 x 10-20
CuS -- 1 x 10-35
FeS -- 1 x 10-17
HgS -- 1 x 10-52
MnS -- 1 x 10-15
NiS -- 1 x 10-19
PbS -- 1 x 10-27
ZnS -- 1 x 10-20

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If he can't figure out that water doesn't freeze in the tropics, do we really think he's going to get the complicated explanation of hydrophobic compounds?What's funny is he says he has a friend in chemistry that told him the world would freeze over if water froze from the bottom up. I suppose this same friend was the one who told him it was a universal solvent.One trip to an organic chem lab would dispell that. Water's nonsolvency on many materials is a great way to separate them into different components based on density.

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holmes
"...what a fool believes he sees, no wise man has the power to reason away.."(D. Bros)

The idea that the oceans would freeze solid if ice sank is based on the idea that once frozen it would not thaw.for it to sink to the bottom it would have to pass through warmer water without thawing and then the bottom would have to be colder than the freezing point.thermal conductivity of the earth means there is alway a flow from the center outward (yes in billions of years the earth will get colder) that keeps the mantle at a temperature well above 32F\0CThis is a fairly accessible geology site that discusses earth temperature and the different layers:
Inside the Earth - Enchanted Learning This site talks about the crust:
http://volcano.und.nodak.edu/...s_layers/Earths_layers4.html Oceanic crust being significantly thinner than continental crust means that there would be more thermal conductivity, more flow of temperature, through the oceanic crust.Ice sinking could actually cause the oceans to be warmer than they are because it would cause more mixing of the water as the thawed bottom ice water would rise to the surface and the ice blocks sank. This would add convection heat transfer into the system.

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we are limited in our ability to understand
by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

Hey don't tell me, tell him! Right now he thinks he has three sources to my just asserting things like water hotter than it's boiling point can't freeze, or that salt prevents freezing, or that it's hot in the tropics.

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holmes
"...what a fool believes he sees, no wise man has the power to reason away.."(D. Bros)

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Ice sinking could actually cause the oceans to be warmer than they are because it would cause more mixing of the water as the thawed bottom ice water would rise to the surface and the ice blocks sank. This would add convection heat transfer into the system.

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Also, we can't forget about the reflectivity of floating ice. Icebergs and floating ice reflect solar energy back out into space. If, for instance, the northern polar ice cap was at the bottom of the ocean the world would be warmer than it is now. Also, surface winds blowing over unfrozen water is warmer than surface winds blowing over ice that is well below 0 celcius (unfrozen sea water is always warmer than about -2 celcius I believe).

yes, based on my experience that would be about right ... we have an annual swim for winter solstice in buzzards bay MA ...

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we are limited in our ability to understand
by our ability to understand RebelAAmerican.Zen[Deist
{{{Buddha walks off laughing with joy}}}

I don't think the proposition that life can only arise in water-based environments was as much off the mark as has been suggested; IIRC Isaac Asimov made that argument in his book on evolution from the 60's, which title I forget. I also think he argued the possibility of methane/silicon life, but also agreed this would be extremely slow-padced life, if possible at all.On sulphur, don't the worms around black smokers use a sulfur-based metabolism?

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I don't think the proposition that life can only arise in water-based environments was as much off the mark as has been suggested;

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I don't think it's far off the mark either. Water is probably the best solvent for life, and it makes a stable byproduct for metabolism. I just have a hard time with the "fine-tuning", anthropic argument.

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On sulphur, don't the worms around black smokers use a sulfur-based metabolism?

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The worms are filter feeders. They feed on autotrophs, some of which metabolize sulfur.