# What is the Temperature of Ice-Water.



## repairman615

Anyone like to share some scientifics and thoughts about the temperature of a ice and water mixture? 

Lets say there is a container of any size. Filled with half water and half ice. What is the tempature.




my coded answer: (triangle line) f.


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## VoG

Once the system comes to equilibrium the temperature should be 0 Celsius.


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## sous2817

What kind of water?  Salt water will freeze at a lower temperature, so you could have a salt water mixture w/ a temp lower than 0 Celsius.


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## repairman615

No salt or other added ingrediants.  Water and Ice at basically the same quantities for reference purposes.

I do beleive you are right, the addition ot salt would lower the frezing point.


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## Colin Legg

At what pressure?


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## repairman615

Normal pressure at about sea-level.

To further the description:

A non-labratory expierment where a container size ranging from a drinking glass to 20 gallon tub.  No lid, open top.

Also as VoG has pointed out, tempature taken after reaching equalibrium.


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## PaddyD

"... tempature taken after reaching equalibrium"

Equilibrium with respect to what? If, for example, that's equilibrium wrt to the environment in the room, then the temperature's going to be whatever the room's temperature is.


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## diddi

there will be temperature gradients throughout the mixture due to energy transfer between the liquid water and the ice and the environment. the change in density of the waters of different temperature will induce convection. even if the ice is at 0c there will be significant energy required to effect the phase change.

all asumptions about about pure water, standard pressure etc still hold.


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## repairman615

PaddyD,

I am thinking that the Ice-and-Water-mix will level off at a temp before most of the Ice has melted. This is the target temp I am looking for.

With Respects to the Ice and water itself. I do not think the room temp would affect the temp of the mix until most of the Ice has melted.


Here is my thoughts:
The Ice and water are mixed, the water temp will begin to drop.
Next, the temp. of the mix will reach a temp. that is not changing.

Target.Here is the number that I am looking for "Temp of Ice and Water"

Next, most of the Ice has melted and the temp begins to rise.
Finally, the mix is now just water and will reach room temp.

Thanks to all here, I really enjoy the intellectual wealth that is here.

Has anyone deciphered my "coded answer" from OP?


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## diddi

is your coded hint suggesting the triple point?


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## Norie

Is it something to do with the phases water/ice go through?


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## repairman615

diddi,
Yes, The points was the key: of a triangle is three and two points in a line.  I think ice water is 32 degrees farenheit or as Vog mentioned, 0 degrees celcius.

Good points to this topic and very interesting to hear the points made be contributers.

Norie,
I suppose, but no secret tricks or anything.  The basic goal here is to gain collective perspectives from the great minds that frequent here.

So far it seems Vog and I are in aggreement as to the temp.  I would like to hear others specific temperature speculations.


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## Norie

What type of ice?


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## diddi

if the solution is agitated, then i am happy with 0c (32F)


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## repairman615

Norie, haha.  Store bought in the 10 or 20 pound bag.


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## diddi

and id be prepared to tip the hint is triangle - 3, line - 2  making 32F


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## repairman615

diddi, that is my guess, you are right. 

I cannot say if my guess is accurate though. hah!


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## diddi

its either that or the triple point which is around 0.1c  not much difference tho in the scheme of things

good idea to have a little light entertainment in the lounge.


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## repairman615

diddi,  I did not know about the triple point as a term.  I just looked up the term and skimmed over, interesting.

It is a coincidence between the using the triangle to represent "three" (points) and the term actually refering to items discussed in this thread.  

Clever!


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## Atroxell

Just to maybe gain some understanding because this physics is outside my realm of knowledge...

It has always been my understanding that a glass of ice water in aan undisturbed environment normally sits around 35 degrees F. I/we frequently use ice water to "calibrate" a thermometer to 35 degrees when we are hunting. Not a scientific device or application, so it does not have to be perfectly precise. But that's what we've always done.

If the water were to cool to 32 degrees, would it not then be ice as well? I do understand and have seen that there are situations where liquid water can be colder and not be a solid, and then flash freeze when agitated, but I am thinking of a simple glass of water sitting on my kitchen table.


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## Norie

Atroxell

I think that was sort of what I was wondering - there isn't just 1 type of 'ice' there's apparently about 15+.

They all have different characteristics, though probably nothing you would notice 9or be bothered about?) outside of a scientific environment.


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## repairman615

Atroxell,

I don't know why I ponder such things as a cup of ice water. I have asked a few friends and family over time, and I always get mixed answers about the temp. Always near the freezing point, 'just below like 31f', 'just above' ranging from 33f to 37f. Some share my perspective.

Water both freezes and melts at 32f or 0c. I think one is absorbing heat and the other way is transfering heat. Until the heat (energy) overcomes one or the other, the temp will stay at a constant 32f... So my hypothesis is that ice and water mixed togather should be 32farenheit.

I found this link below and the horse of a different color is that boiling water is 212f...and remains that temp... Similar to the topic yet on a tangent.

Check this out.
<TABLE style="WIDTH: 230pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=307><COLGROUP><COL style="WIDTH: 230pt; mso-width-source: userset; mso-width-alt: 11227" width=307><TBODY><TR style="HEIGHT: 15pt" height=20><TD style="BORDER-BOTTOM: #f0f0f0; BORDER-LEFT: #f0f0f0; BACKGROUND-COLOR: #c2d69a; WIDTH: 230pt; HEIGHT: 15pt; BORDER-TOP: #f0f0f0; BORDER-RIGHT: #f0f0f0" class=xl65 height=20 width=307>Here is a link to time-temp study</TD></TR></TBODY></TABLE>


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## MrKowz

Water, when in the process of becoming a solid, or in the process of becoming a liquid, is 32°F (0°C). The process it is going through at this point is a transition phase. It takes a LOT of energy to complete this phase, which is why it takes so long. The energy used to accomplish this task is known as the "latent heat of fusion". Which, under STP (standard temperature and pressure), is 333 J/g. 

Here is a graph which depicts this:

http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/phase.html

However, when you say "a glass of ice-water", then you have other factors that come into play. The ambient heat around the glass affects the temperature. Outer layers of molecules will be warmer than 32°F (0°C), and inner layers will maintain the 32°F (0°C) temperature. Also, as indicated earlier, how well "mixed" it is also affects it. It will not churn itself (like a pot of boiling water does), so if it is under a consistent stir with a rod that maintains a consistent temperature of the solution it is in, then the ice-water combination should, and will, maintain a consistent 32°F (0°C) until it either becomes frozen, at which point it will become colder, or until it becomes all liquid, at which point it will become warmer. Although one could argue that the process of stirring creates friction, which increases temperature.


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## Atroxell

So, for my purposes, it is probably safe for me to say that the ice-water is approximately 35 degrees.

The ice in the glass is 0 degrees, or it would be liquid.

And the environment outside the glass could be 7, 70 or 700 degrees, which would make the water/ice react differently. If the temperature outside the glass should dip below 32 degrees F, then the water would (eventually) transition to solid form.

So the final determining factors to the temperature of a mixture of ice and water would be:
1) the ambient temperature of the environment _around_ the container, and
2) the volume of the ice and water (which might influence how long it would take for the ice or water to transition between states, whether water to ice or ice to water), and
3) at what point in time you measure the temperature.

And there might be something to add with respect to the material of the container--I would think that it makes a difference whether it's a glass material of a styrofoam cup.

I think this discussion could go on almost forever unless someone specifically chooses the *precise* circumstances under which the ice water exists.


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## diddi

@MrKows
the friction of agitation only contributes to the temperature after the phase change. prior to that it merely accelerates the transition.

@Atroxell
1) ambient temp only affects RATE of change of ice-water not the temp of the mix
2) volume is irrelevant (except if it is so small that the warm thermometer actually melts all the ice
3) if the mix is agitated, then the time is irrelevant also

the issue for you is that 'in the field' you need to be very specific about where in the mix the thermometer is positioned. as i stated in an earlier post, the mix is awash with temp gradients. so chucking a few cubes in a cup and filling it with water and waiting 5 mins then dropping the thermometer into the bottom will undoubtedly give a high reading, similarly if its all ice and not much water, and the thermometer is in direct contact with a cube, then the result will read low.  the experimental conditions dictate that
a) the mixture is agitated
b) the temp is measured in close proximity to the ice but not touching it.

under experimental (lab) conditions, the temp will be 32F 0c

oh BTW, you can have water (liquid) ot 32F and also ice at 32F.   32F is the point at which it CHANGES either way to the other state.


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## Long Nose

I agree with the 32 degrees remark above, but if it is indoors at my house it will steady go up from there.

If ice water is 32 degrees once at the momentary desired equilibrium, what temperature would the same glass of Gin and ice be at the same momentary equilibrium? 

(I did not say scotch, as I did not wish to offend any true whisky drinkers.)


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## VoG

A glass of gin and ice does not last long enough in my presence for me to measure its temperature


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## diddi

and i find a complete loss of equilibrium when gin is involved, particularly if the experiment is repeated several times.


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## TinaP

The experiment must, however, be repeated so that we can determine if there is a range of temperatures or continued loss of equilibrium.


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