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Phi Phi Do 2E
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Joined: Fri Sep 29, 2017 7:05 am


Postby Phi Phi Do 2E » Thu Jan 11, 2018 10:11 pm

Can somebody explain to me more about the concept of sublimation?

Matthew Lin 2C
Posts: 30
Joined: Fri Sep 29, 2017 7:06 am

Re: Sublimation

Postby Matthew Lin 2C » Thu Jan 11, 2018 10:29 pm

Sublimation is when a substance changes from a solid directly to a vapor, effectively skipping the liquid phase. This obviously isn't super common, but a well-known example is dry ice. I would say an important concept to know is that the enthalpy of sublimation can be calculated with the sum of the enthalpies of fusion and vaporization. This is true because enthalpy is a state function. An interesting fact is that the reverse of sublimation is called deposition, which is when a substance changes from a vapor directly to a solid.

Sophie 1I
Posts: 51
Joined: Fri Sep 29, 2017 7:04 am

Re: Sublimation

Postby Sophie 1I » Thu Jan 11, 2018 10:32 pm

Sublimation is a type of phase transition of a substance from solid to vapor without going through the liquid phase.

Michelle Lu 1F
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Re: Sublimation

Postby Michelle Lu 1F » Sun Jan 14, 2018 1:24 am

Sublimation by definition is the physical transition between the phases solid and vapor. This is a direct change between these two phases without going through the liquid phase. Dry ice at normal room temperature is a common example of sublimation.

Julianna Thrasher 1B
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Joined: Thu Jul 27, 2017 3:00 am

Re: Sublimation

Postby Julianna Thrasher 1B » Sun Jan 21, 2018 5:14 pm

Sublimation is an endothermic reaction. This means that when a solid transforms into vapor, the enthalpy is positive and heat is required for the transformation. For dry ice, the most obvious example of sublimation, the dry ice feels cool because the ice is taking the heat from the surroundings in order to transform from solid to vapor.

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