Latent heat effects thermal equilibrium

AI Thread Summary
When mixing ice at 0 degrees Celsius with water at 80 degrees Celsius, the final temperature can remain at 0 degrees if both substances have the same mass due to the latent heat of fusion. The heat from the warmer water is used to convert the ice into water without raising the temperature above 0 degrees. This process requires approximately 80 calories of energy per gram of ice to complete the phase transition. In a perfectly insulated container, all the heat from the water can be absorbed by the ice, resulting in a final equilibrium temperature of 0 degrees. This phenomenon highlights the significant role of latent heat in thermal exchanges.
saykaof
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Can anyone explain that how the ice's temperature is zero degree and water's temperature is 80 degree are mix and their final temperature is zero degree if the both ice and water has the same mass?

Where:
mc(delta T) of water = (mc(delta T) + mL ) of ice
the result for final temperature is 0 degree but how can it be?

This is telling me that if I have a perfect insulation container then every drop of water at 80 degree can be zero degree as long as the intial mass is the same, is it true?
 
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saykaof said:
Can anyone explain that how the ice's temperature is zero degree and water's temperature is 80 degree are mix and their final temperature is zero degree if the both ice and water has the same mass?
Because water has a latent heat. At normal pressure, you need around 80 cal to transform 1 g of 0°C ice into 0°C water, which is the heat needed to cool off 1 g of water by 80°C.
For further reading : http://en.wikipedia.org/wiki/Enthalpy_of_fusion.
 
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Absolutely wonderful for both the question and solution.

It's delightful for me, too, to realize that all that 80 celcius worth of kinetic energy in water are absorbed by the ice in order to cause a phase transition from 0 celcius solid to 0 celcius liquid.

It'd be wonderful to see this in reality, only if i have the tool to precisely control the temperature and mix them with near perfect isolation.
 
You can do the experiment in a thermos easily enough.
 
Thanks all for your explanation, they were simple enough for me to understand my problem.
 
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