Phase Changes
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Phase Changes
I'm still kind of confused on why the temperature does not change when a substance is undergoing a phase change? Is it because the heat being absorbed is being used to break bonds so it doesn't affect the overall temperature?
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Re: Phase Changes
Yes, you are correct. Since the energy involved in phase changes is used to break bonds, there is no increase in temp or kinetic energy.
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Re: Phase Changes
Rather than the temperature increasing as heat is supplied, the incoming heat is instead being used to break bonds and thus there will not be temperature change during a phase change transition.
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Re: Phase Changes
Yep! The heat being supplied is going into breaking the intermolecular forces (e.g. H bonds, LDFs, etc) between molecules rather than increasing the temperature of the molecules.
Re: Phase Changes
That's correct. The energy goes to breaking the intermolecular forces between the molecules instead of to changing the temperature.
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Re: Phase Changes
To add on, because it's a phase change it will a change in potential or positional energy rather than kinetic energy, which includes temperature alongside mass. Thus, when water phase changes into ice, we know that there will not be a change in kinetic energy or change in temperature. This could easily be observed if you look at a heating or cooling curve for water. I hope this helps!
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Re: Phase Changes
Yes, Because at that temperature the amount of extra heat which is being supplied to the substance is used in Breaking the intermolecular forces so the temperature remains constant and the until the state of matter changes the heat is used to break intermolecular forces and hence after the breaking of intermolecular forces.
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Re: Phase Changes
You're correct! The temperature does not change when a substance is undergoing a phase change, because the heat energy supplies is used to break bonds or the intermolecular forces of molecules. In addition, the kinetic energy doesn't change either. Hope this helps!
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Re: Phase Changes
Yep, you're right! The heat is used to break bonds, hence the name "bond enthalpies," so there's no heat leftover to induce any changes on temperature or overall kinetic energy.
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Re: Phase Changes
Exactly! The heat energy is just being used up for the phase change that there isn't any extra to change the temperature of the system.
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