# Freeze? Turns into gas?

1. Dec 25, 2007

### kudoushinichi88

Let's say you have water in liquid form in a closed container on a spaceship in space. Then you bring the container filled with water out from the space ship into free space.

Will the water freeze, stay in liquid form or turn into gas?

Assume the container didn't break.

Last edited: Dec 25, 2007
2. Dec 25, 2007

### ozymandias

Assuming the container wouldn't break, the water would stay in liquid form.
The pressure stays the same and the temperature doesn't change as well, so no phase transition for you :).

-----
Assaf
"www.physicallyincorrect.com"[/URL]

Last edited by a moderator: Apr 23, 2017
3. Dec 25, 2007

### kudoushinichi88

Oh, the temperature inside the ship and outside the ship is the same?

4. Dec 25, 2007

### ozymandias

Once outside the water has no way of transferring heat - not by convection, nor by conduction (to what? there is nothing in space). It will radiate, but it would take it a looong amount of time to lost its heat energy that way.

5. Dec 25, 2007

### kudoushinichi88

6. Dec 25, 2007

### Staff: Mentor

It actually doesn't take that long to radiate heat away. If shaded from the sun, it could freeze in a few hours. If not shaded from the sun, solar radiation would probably keep it warm (though I'd have to calculate that to be sure).

7. Dec 25, 2007

### kudoushinichi88

So the water can, in fact be either in solid, liquid or gaseous state depending on how much is the container shaded from the sun?

8. Dec 25, 2007

### ozymandias

Ah, never said anything about the sun :).
Exactly how far from the sun are we talking about?
(and we ARE talking about OUR sun, right?)

Assaf
"www.physicallyincorrect.com"[/URL]

Last edited by a moderator: Apr 23, 2017
9. Dec 25, 2007

### GT1

As far as I know all material emit electromagnetic radiation because they contain charged particles which accelerate at random directions because of the thermal energy the object has.
If you have an object in a perfect vacuum far far away from any other objects,
why shouldn't it emit electromagnetic radiation ? as i see it - it emits the radiation because of its own properties and not only because of the environment.
I think it even should be cooled faster if it has no other object around it which can reflect back the radiation it emits, or radiate energy back to it.
Does it make sense what I say ?

10. Dec 25, 2007

### dst

The water will not change if the container retains its volume, regardless of any influences.

If the container changes volume then it's a whole different ballpark.

11. Dec 25, 2007

### MaWM

eh?

Anyway.. as other people said. What happens to it depends on how much radiation it receives.

12. Dec 26, 2007

### uart

Yes this question has way too many undefined parameters to have any meaningful answer, though you could consider a few specific cases.

Case 1. Water in the dark of space in a closed container.

In remote space it is very cold (about 3 degrees k background radiation) so yes the water would cool and freeze if contained in a closed container. The radiative cooling need not be that slow.

Take for example 1 litre of water enclosed in a 10cm per side cube as an example. If the wall material radiates somewhere close to a blackbody then the rate of loss of energy at say 10C (283k) is about 5.7E-8 * 600E-4 * 283^4, which comes to about 21 Joules per second. One litre requires 1000 Joules per degree C of cooling so thatâ€™s about one degree every 50 seconds. For a very rough calculation if the one litre started at around 20C to 25C then it could freeze in as little as about 20 minutes.

Case 2. Water in the dark of space in an open container.

Space is close to a vacuum, certainly less than the triple point pressure (about 600 Pa) for water, so an open container of water (at say 20C) would immediately boil if removed from the pressurized space-craft into the (near) vacuum of space. In fact it may even boil and freeze at the same time. That is, it might not boil away completely but instead to partially boil away while leaving a frozen residue (that would eventually sublimate (convert directly from solid ice to water vapour).

Last edited: Dec 26, 2007
13. Dec 26, 2007

### kudoushinichi88

Ah, I understand now that water freezes in space far influences such as the sun.

Now I'm interested in the case where our container is somewhere in a geosynchronous orbit above the earth. Will the water stay in liquid form when facing the sun? Will it freeze when earth is blocking the sun?

14. Dec 26, 2007

### DaveC426913

Question:Does the water have room to expand and contract as it changes state? Is the container rigid enough to defeat this or allow it?

If the container resists expansion and contraction, the water will remain in whatever state it started in.

15. Dec 26, 2007

### kudoushinichi88

Okay, let's assume that the container is full with water and it's rigid and indestructible. So, from my understanding of your post is that the water will stay in liquid form even when sunlight shines upon it?

16. Dec 26, 2007

### MaWM

No.. the water will eventually vaporize then plasmarize if the temperture gets high enough.

17. Jan 2, 2008

### kudoushinichi88

Plasmarize?

Okay, let's make give the details of the problems...

Case 1: A rigid, indestructable, transparent, air tight container full with water is floating in deep dark space far from the sun. Initially the water is in liquid form at temperature 25 degrees celcius. Will the water continue to be in liquid form or will it freeze or turn into gas?

From the answers given in previous posts, I understand that the water will radiate away it's heat and freeze in a few hours. Correct?

Case 2: A rigid, indestructible, transparent, air tight container full with water is floating in space. Initially the water is in liquid form at temperature 25 degrees celcius. But this time, it receives radiation from the sun.

Now this one... depending on the amount of radiation, the water will either stay in liquid form or freeze? Since the container full of water and not expandable, the water cannot turn into gas, correct?

Case 3: A rigid, indestructible, transparent, air tight container full with water is floating in deep dark space far from the sun. Initially the water is in liquid form at temperature 25 degrees celcius. This time, the cover of the container is opened. What will happen?

18. Jan 3, 2008

### DaveC426913

In case 1, the water will stay in liquid form. We see this happen all the time. Water under pressure stays liquid even if heated above the boiling point. Happens in a pressure cooker and undersea thermal vents.

In case 2, the water will stay on liquid form. Water under pressure cannot crystalize, so its stays liquid.

In case 3, the water will boil away. While it's cold enough to normally cause it to freeze, there's no pressure to keep the molecules of water from simply floating away.

19. Jan 3, 2008

### MaWM

Correct

Incorrect. If it gets hot enough, it can turn to gas without expanding. We can go all out and place the indestructible container in the core of the sun. The matter there is 150 times more dense than water on earth, and yet it is plasma.

In this case, part of the water would boil immediately, supercooling the rest and leaving behind a hunk of ice.

20. Jan 3, 2008

### kudoushinichi88

How can something turn into gas without expanding? The water in the container if heated, wouldn't display the characteristics of a gas, would it? Does that mean it will turn into plasma without going through the gas state?

21. Jan 3, 2008

### nanoWatt

22. Jan 3, 2008

### DaveC426913

Bad comparison. Liquid nitrogen is nothing like the vacuum of space:
1] It has pressure. Vacuum does not.
2] It takes heat by conduction. Vacuum allows only radiative heat transfer. (And, I suppose, ablative heat transfer)

23. Jan 3, 2008

### DaveC426913

Say, I've always understood that there are only 3 methods of heat transfer: convective, conductive and radiative. Could ablative be considered a fourth?

24. Jan 3, 2008

### MaWM

That's only true for tempertures close to the freezing point. As ice cools, it contracts, until eventually its density is lower than that of water. At this temperture, water can crystalize to ice without expanding beyond its orginal volume. Beyond that, water has several different solid states. If the water is cooled quickly enough (admittedly, that would not be the case here), it can freeze into amorphous ice. In that case, no cryallization is required.

Last edited: Jan 3, 2008
25. Jan 3, 2008

### Staff: Mentor

I have wondered that same question before, although I would probably call it something like "state change" rather than "ablative" because "ablative" sounds like it would specifically apply to evaporation and melting, but not condensation and freezing or crystalization.

I think that the key difference between convection, conduction, and radiation and state changes is that the former three can act without a mass transfer, i.e. they are purely energy transfer. On the other hand evaporation etc. are necessarily mass as well as energy transfer mechanisms.