Temp in Phase Change

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Priscilla Tamborini 1B
Posts: 9
Joined: Wed Nov 18, 2015 3:00 am

Temp in Phase Change

Postby Priscilla Tamborini 1B » Sun Jan 15, 2017 9:25 pm

Can someone elaborate on why the temperature doesn't change during a phase change? How can there be a change in heat without a change in temp?

Priscilla_Molina_3J
Posts: 9
Joined: Fri Jul 22, 2016 3:00 am

Re: Temp in Phase Change

Postby Priscilla_Molina_3J » Sun Jan 15, 2017 9:39 pm

Because that heat is being used to break the intermolecular bonds which then causes the phase changes (for example: with water, from solid to liquid, the heat is breaking up the bonds between the H20 molecules that were compacted, making the molecules shift around more, which causes the eventual change to liquid)

Shadi_Keyvani_1D
Posts: 27
Joined: Wed Sep 21, 2016 2:56 pm

Re: Temp in Phase Change

Postby Shadi_Keyvani_1D » Sun Jan 15, 2017 9:40 pm

Changing the amount of heat energy usually causes a temperature change. However, during the phase change, the temperature stays the same even though the heat energy changes. This energy is going into changing the phase and not into raising the temperature. This means that there is a constant temperature as the phase change takes place.

Lauren_Johnston_3F
Posts: 12
Joined: Fri Jun 17, 2016 11:28 am

Re: Temp in Phase Change

Postby Lauren_Johnston_3F » Sun Jan 15, 2017 10:05 pm

Temperature is the average kinetic energy of particles and indicates the random motion of particles. Heat is a form of energy that transfers between two substances due to a temperature difference. During a phase change heat is used to break the bonds between molecules to change the state of the substance. An example is when heat is used to break the bonds between ice molecules during a phase change into water (melting). The average kinetic energy does not change at the instance of melting. Therefore the temperature of the molecules does not change, but rather the bond energy changes between molecules.


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