Phase change

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itzeelpadillaDis1A
Posts: 52
Joined: Fri Sep 29, 2017 7:03 am

Phase change

Postby itzeelpadillaDis1A » Fri Feb 02, 2018 11:58 am

How do we know when to do a phase change like on #7 on test 1?

Kaileigh Yang 2I
Posts: 49
Joined: Sat Jul 22, 2017 3:00 am

Re: Phase change

Postby Kaileigh Yang 2I » Fri Feb 02, 2018 12:43 pm

You know the phase change would occur because it's changing from a solid to a liquid. It is not only increasing in temperature, the heat required to change the physical form of the substance would need to be taken into account as well.

Clement Ng
Posts: 73
Joined: Sat Jul 22, 2017 3:00 am
Been upvoted: 3 times

Re: Phase change

Postby Clement Ng » Fri Feb 02, 2018 1:19 pm

Usually when temperature is constant and no chemical reaction is occurring.

Kyra LeRoy 1E
Posts: 52
Joined: Sat Jul 22, 2017 3:00 am

Re: Phase change

Postby Kyra LeRoy 1E » Fri Feb 02, 2018 1:54 pm

You'll know to do a phase change when it hits the temperature for fusion or vaporization. I think normally these questions will have to do with ice/water because the melting point is 0 degrees Celsius and boiling is 100 degrees, and so its a pretty straightforward/easy one to remember. If it is ice at 0 degrees then you know you must work with melting, and if it is liquid at 100 degrees you know you have to deal with vaporization.

Pooja Nair 1C
Posts: 55
Joined: Thu Jul 13, 2017 3:00 am

Re: Phase change

Postby Pooja Nair 1C » Wed Feb 07, 2018 11:13 am

You can usually tell it's a phase change from the question either explicitly stating it or from the information given. I think these questions are usually about water, because we already know the melting/freezing point. In the case of #7, since you have a cube of ice at 0.0 Celsius, which is the freezing point, reacting with the tea/water which is at a higher temperature, you can expect melting of the ice cube, as any heat transferred to it will raise the temperature above 0 Celsius.


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