phase changes, temperature constant?

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Alexandra Bartolome 2H
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Joined: Sat Jul 20, 2019 12:17 am

phase changes, temperature constant?

Postby Alexandra Bartolome 2H » Sun Feb 02, 2020 10:35 pm

During phase transition, why does the temperature of the sample remains constant even though heat is being supplied?

lilymayek_1E
Posts: 107
Joined: Sat Aug 17, 2019 12:16 am

Re: phase changes, temperature constant?

Postby lilymayek_1E » Sun Feb 02, 2020 11:10 pm

heat remains constant during a phase change because heat is being supplied to the phase change mechanism itself, not to the actual heating of the subject being heated. heat is being used in creating the phase change at the same rate that it's being applied to the actual material, so the heat remains constant.

Sam McNeill 1E
Posts: 110
Joined: Sat Aug 24, 2019 12:17 am

Re: phase changes, temperature constant?

Postby Sam McNeill 1E » Mon Feb 03, 2020 4:50 pm

The temperature remains the same because all of the energy from the heat is being used to transition the substance into the next phase.

Qiu Ya Wu 4I
Posts: 107
Joined: Fri Sep 20, 2019 12:17 am

Re: phase changes, temperature constant?

Postby Qiu Ya Wu 4I » Mon Feb 03, 2020 5:17 pm

In addition, you can think of the temperature remaining the same due to all the added heat being used to break the bonds between molecules of a substance.

CosetteBackus_4F
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Joined: Wed Feb 20, 2019 12:18 am

Re: phase changes, temperature constant?

Postby CosetteBackus_4F » Tue Feb 04, 2020 12:52 pm

Heat is necessary for the phase change to occur so the heat being supplied is being used to break the bonds and does not contribute to the heat of the substance itself.

Joanne Lee 1J
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Joined: Thu Jul 25, 2019 12:15 am

Re: phase changes, temperature constant?

Postby Joanne Lee 1J » Tue Feb 04, 2020 10:49 pm

The temperature of the sample remains constant even though heat is being supplied because all the energy is being used to change the substance phase, not alter the temperature of the sample.

Shutong Hou_1F
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Joined: Sat Sep 14, 2019 12:17 am

Re: phase changes, temperature constant?

Postby Shutong Hou_1F » Sat Feb 08, 2020 12:03 am

The change of a substance from a phase of a lower energy to a phase of a higher energy requires heat to break intermolecular interactions between molecules, thereby making the substance have higher potential energy between molecules (usually, the volume of a substance: solid state < liquid state < gas state).

Radha Patel 4I
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Joined: Tue Feb 12, 2019 12:15 am

Re: phase changes, temperature constant?

Postby Radha Patel 4I » Sat Feb 08, 2020 9:13 am

The heat of the bonds to break the substance are being supplied while the temperature does not change to allow the phase change to occur

Zoe Gleason 4F
Posts: 51
Joined: Tue Jul 23, 2019 12:15 am

Re: phase changes, temperature constant?

Postby Zoe Gleason 4F » Sat Feb 08, 2020 10:21 am

The temperature remains constant because the energy is going towards the phase change itself, and will therefore not heat the system.

Jessica Kwek 4F
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Joined: Mon Jan 06, 2020 7:57 am

Re: phase changes, temperature constant?

Postby Jessica Kwek 4F » Sat Feb 08, 2020 1:54 pm

Temperature remains constant during phase change because heat energy is stored as potential energy.

Sydney Pell 2E
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Joined: Wed Sep 11, 2019 12:17 am

Re: phase changes, temperature constant?

Postby Sydney Pell 2E » Sun Feb 09, 2020 4:53 pm

When heating a substance, for example, water, the heat energy is used to first raise the temperature to the boiling point. When the temperature gets to that point, the heat energy is then used to complete the phase change instead of raising the temperature further. So, the boiling water would stay at 100 C while using the heat energy to convert its molecules to the gas phase instead.

Manav Govil 1B
Posts: 104
Joined: Sat Sep 07, 2019 12:19 am

Re: phase changes, temperature constant?

Postby Manav Govil 1B » Sun Feb 09, 2020 5:21 pm

An increase in heat energy is not the same thing as an increase in temperature (delta H is different than T). Therefore it is possible for heat energy to be introduced to the system and for the temperature to not increase.


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