Latent heat effects thermal equilibrium

In summary, when ice and water with the same mass are mixed, their final temperature will be zero degrees Celsius. This is because water has a latent heat and it takes about 80 calories to transform 1 gram of 0°C ice into 0°C water. This means that the heat from the water at 80°C is transferred to the ice to cause a phase transition from solid to liquid. This can be seen in an experiment with precise temperature control, such as in a thermos.
  • #1
saykaof
2
0
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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  • #2
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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  • #3
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.
 
  • #4
You can do the experiment in a thermos easily enough.
 
  • #5
Thanks all for your explanation, they were simple enough for me to understand my problem.
 

1. What is latent heat?

Latent heat is the amount of energy that is absorbed or released by a substance during a phase change without a change in temperature. It is the energy required to change the state of matter from solid to liquid or liquid to gas, and vice versa.

2. How does latent heat affect thermal equilibrium?

Latent heat plays a crucial role in thermal equilibrium as it is responsible for maintaining the temperature of a substance during a phase change. When the substance absorbs heat and undergoes a phase change, the temperature remains constant until the phase change is complete. This helps to maintain thermal equilibrium in a system.

3. What is the difference between latent heat and specific heat?

Latent heat and specific heat are both measures of energy, but they differ in the way they affect temperature. Specific heat is the amount of heat required to raise the temperature of a substance by a certain amount, while latent heat is the amount of heat required to change the phase of a substance without a change in temperature.

4. How does the amount of latent heat vary between different substances?

The amount of latent heat required for a phase change depends on the substance and the type of phase change. For example, water has a relatively high latent heat of vaporization compared to other substances, meaning it requires more energy to change from liquid to gas. This is due to the strong hydrogen bonds between water molecules.

5. How does latent heat affect the Earth's climate?

Latent heat plays a crucial role in regulating the Earth's climate. The evaporation of water from the Earth's surface absorbs a large amount of latent heat, which is released when the water vapor condenses in the atmosphere, helping to regulate the temperature. Changes in the amount of water vapor in the atmosphere can have a significant impact on the Earth's climate and weather patterns.

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