Phase change and temp

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Lindsey Chheng 1E
Posts: 110
Joined: Fri Aug 30, 2019 12:16 am

Phase change and temp

Postby Lindsey Chheng 1E » Tue Jan 28, 2020 10:33 pm

why does the temperature remain constant during a phase change?

Caitlyn Tran 2E
Posts: 100
Joined: Fri Aug 09, 2019 12:15 am

Re: Phase change and temp

Postby Caitlyn Tran 2E » Tue Jan 28, 2020 10:41 pm

The temperature remains constant during a phase change because the energy is used to break bonds to change the phase rather than to change the temperature. Hope this helps!

Minh Ngo 4G
Posts: 137
Joined: Thu Jul 25, 2019 12:17 am

Re: Phase change and temp

Postby Minh Ngo 4G » Tue Jan 28, 2020 11:36 pm

Because all the energy are being used to either break a bond or form a bond, thus no energy is used for heating up the material

Brooke Yasuda 2J
Posts: 102
Joined: Sat Jul 20, 2019 12:17 am

Re: Phase change and temp

Postby Brooke Yasuda 2J » Wed Jan 29, 2020 12:59 am

remember it is not technically breaking bonds, as in covalent bonds between Hydrogen and Oxygen molecules. It is breaking intermolecular forces between water molecules. Therefore, energy is needed to overcome and break the intermolecular forces which requires heat.

Miriam Villarreal 1J
Posts: 105
Joined: Sat Aug 17, 2019 12:16 am

Re: Phase change and temp

Postby Miriam Villarreal 1J » Wed Jan 29, 2020 7:59 am

During the phase change, when solid melts into liquid, its temperature remains constant as the heat energy is stored as potential energy.

andrewcj 2C
Posts: 102
Joined: Thu Jul 11, 2019 12:17 am

Re: Phase change and temp

Postby andrewcj 2C » Wed Jan 29, 2020 9:50 am

It is important to distinguish between breaking bonds and breaking the intermolecular attractions between molecules in a substance. During phase changes, the chemical bonds in the molecules of the substance aren't actually being broken. Rather, the energy added is being used to break the attractions between molecules in the substance. However the substance remains the same, so when water is evaporated it doesn't turn into H2 and O, it stays H2O.

Rida Ismail 2E
Posts: 139
Joined: Sat Sep 07, 2019 12:16 am

Re: Phase change and temp

Postby Rida Ismail 2E » Wed Jan 29, 2020 11:26 am

The temperature stays the same because the energy going into the system is used to change the phase of the substance and not increase the temperature. Once the phase change is complete the temperature starts rising again.

VioletKo3F
Posts: 103
Joined: Sat Sep 07, 2019 12:18 am

Re: Phase change and temp

Postby VioletKo3F » Wed Jan 29, 2020 11:39 am

Energy is used for the phase change, so there is no increase/decrease in temperature.

Kayli Choy 2F
Posts: 100
Joined: Sat Aug 24, 2019 12:17 am

Re: Phase change and temp

Postby Kayli Choy 2F » Wed Jan 29, 2020 3:25 pm

Additionally, more heat energy is required to break bonds when a substance is vaporizing (liquid to gas) as opposed to when a substance is melting (solid to liquid) because bonds have to be completely broken in the gas phase.


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