Has there been an improved understanding of water ?

[Aqueous Id]

But the question remains

How does H2 and O become liquid because of their bonds at much higher temperatures , such as room temps.

If this question has been answered , I don't see it

There are two kinds of bonds to consider. The one that joins 2H[sup]+[/sup] with O[sup]2-[/sup] is strong, and involves large amounts of energy. It's not in play here.

The second kind is the Hydrogen bond which is due to a weak force (Van der Waals) between water molecules. When water freezes and thaws, it's this Hydrogen bond which will break and reform under cooling and heating.

It's not H[sub]2[/sub] and O (?) changing phase, only H[sub]2[/sub]O. Note: H[sup]+[/sup], O[sup]2-[/sup], H[sub]2[/sub], O[sub]2[/sub] and H[sub]2[/sub]O are different chemicals, with entirely different properties. If you look at a table of melting points for various compounds and compare them to the bond energies involved in the formation of those compounds, you'll notice there is no correlation.

 

[arauca]

High density water?
Do you mean heavy water?

not D20

 

[exchemist]

But the question remains

How does H2 and O become liquid because of their bonds at much higher temperatures , such as room temps.

If this question has been answered , I don't see it

River, I'm struggling to see what it is you do not understand here. Hydrogen burns to form water because the bond energies in water are stronger than in the hydrogen and oxygen molecules that are replaced: 2 H₂ + O₂ -> 2 H₂O. Water condenses at temperatures <100C (at normal pressure) because there are also these hydrogen bonds, which are stronger than the attraction between most light molecules.

What is the problem, exactly?

 

[arauca]

I think this is a fancy way to say that water is a polar molecule and the electro-static forces hold them together better (liquid at a higher temperature) than non-polar molecules like CO2 or CH4.

If I would make comparison of water I would do it with H2S here the Mw twice of water jet is a gas at R.T. Formula: H2S
Density: 1.36 kg/m³
Molar mass: 34.0809 g/mol
Boiling point: -76°F (-60°C)
Melting point: -115.6°F (-82°C
Electronegativity for S 2.59
" for O 3.4

What I would say the Hydrogen in water is held by more then one molecule of water and water should have a structure as a quasi crystalline

 

[KitemanSA]

High density water?
Do you mean heavy water?

No, not heavy water, Polywater.

Polywater was a hypothetical polymerized form of water that was the subject of much scientific controversy during the late 1960s. By 1969 the popular press had taken notice, to the point that it was used as a plot device in Star Trek, and sparked fears of a "polywater gap" in the USA.

 

[wellwisher]

At room temperature, the attraction between oxygen molecules O2 or hydrogen molecules H2 is weak, such that entropy, which among other things, is connected to disorder, is stronger causing these to be gases at room temperature. To make them liquify, we need to lower the temperature, to remove heat energy away from the entropy, so their weak attractive forces can begin to dominate to form a liquid.

With water or H2O, the hydrogen bonding between oxygen and hydrogen is so strong that at the same ambient conditions, the entropy is not able to overcome to make water a gas, except as partial pressure vapor above the liquid, The result is water is a liquid.

In terms of an equation we have G = H -TS where G is the free energy, H is the enthalpy, T is the temperature, and S is entropy. With O2 and H2, the TS term is dominate because the weak attractive forces or H between O2 or H2, is tiny. With water H is huge and TS is small by proportion.

This huge H contribution in liquid water is important to life since it helps push the organics of life into order by making their TS smaller by comparison. We shake water and oil and add energy the entropy will increase to form an emulsion. But shortly the H will take over and lower the entropy/disorder until only two layers remain.

 

[river]

At room temperature, the attraction between oxygen molecules O2 or hydrogen molecules H2 is weak, such that entropy, which among other things, is connected to disorder, is stronger causing these to be gases at room temperature. To make them liquify, we need to lower the temperature, to remove heat energy away from the entropy, so their weak attractive forces can begin to dominate to form a liquid.

With water or H2O, the hydrogen bonding between oxygen and hydrogen is so strong that at the same ambient conditions, the entropy is not able to overcome to make water a gas, except as partial pressure vapor above the liquid, The result is water is a liquid.

In terms of an equation we have G = H -TS where G is the free energy, H is the enthalpy, T is the temperature, and S is entropy. With O2 and H2, the TS term is dominate because the weak attractive forces or H between O2 or H2, is tiny. With water H is huge and TS is small by proportion.

This huge H contribution in liquid water is important to life since it helps push the organics of life into order by making their TS smaller by comparison. We shake water and oil and add energy the entropy will increase to form an emulsion. But shortly the H will take over and lower the entropy/disorder until only two layers remain.

Are you saying that entropy is a force ?

 

[Russ_Watters]

Yes

How both hydrogen and oxygen become liquid at room temps.

When both ONLY become liquid , separately , at extreme cold temps

-256 and -236 respectively

I don't think you are understanding what a molecule is. A molecule is the smallest unit of a substance that retains/determine its chemical properties: the macroscopic properties we observe such as color and boiling temperature. So water and molecular oxygen are completely different molecules, which means their boiling points should not be expected to be related in any way at all.

http://en.wikipedia.org/wiki/Molecule

 

[river]

I don't think you are understanding what a molecule is. A molecule is the smallest unit of a substance that retains/determine its chemical properties: the macroscopic properties we observe such as color and boiling temperature. So water and molecular oxygen are completely different molecules, which means their boiling points should not be expected to be related in any way at all.

http://en.wikipedia.org/wiki/Molecule

I don't get what saying here

Water is H2 - O

There is no molecule of O2

 

[origin]

There is no molecule of O2

Yes there is - that is the stuff in the atmosphere that is keeping you alive. A molecule of $$O_2$$ is made up of 2 oxygen atoms.

 

[river]

Yes there is - that is the stuff in the atmosphere that is keeping you alive. A molecule of $$O_2$$ is made up of 2 oxygen atoms.

We are discussing water here though , not the atmosphere

 

[origin]

We are discussing water here though , not the atmosphere

Geeze, this is your thread. You started the thread talking about H2, O2 and H2O not just water. So, do you get why there is the difference in the boiling points?

 

[river]

Geeze, this is your thread. You started the thread talking about H2, O2 and H2O not just water. So, do you get why there is the difference in the boiling points?

Sure because of atmospheric pressure

So we still don't know whether H and O , so a single atom of each has the ability to form a liquid on there own ?

Interesting

 

[origin]

Sure because of atmospheric pressure

Ha ha, no need to be sarcastic.

 

[river]

Ha ha, no need to be sarcastic.

Sarcastic ?

 

[Russ_Watters]

So we still don't know whether H and O , so a single atom of each has the ability to form a liquid on there own ?

Interesting

H and O are diatomic molecules. They do not exist as single molecules in either their normal liquid or gas forms.

 

[river]

H and O are diatomic molecules. They do not exist as single molecules in either their normal liquid or gas forms.

Yes but it would be interesting to find out whether both H or O could on their own , single atoms , produce a liquid state

 

[arauca]

Yes but it would be interesting to find out whether both H or O could on their own , single atoms , produce a liquid state

if you mean a free radical O and a free radical H, I would think the half life of such radical would be very short and they will become ionized into O- and H+

 

[river]

if you mean a free radical O and a free radical H, I would think the half life of such radical would be very short and they will become ionized into O- and H+

Yes I suggest free radical

So your saying that a lone H atom or O atom cannot survive alone , but we don't know this , its a thought rather than knowing

 

[arauca]

Yes I suggest free radical

So your saying that a lone H atom or O atom cannot survive alone , but we don't know this , its a thought rather than knowing

I think because the nature of electronegativity of oxygen it will get the electron from some of its surrounding or it will interact with an other oxygen to share its unfilled orbital .