Midterm Practice #2C

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Nha Dang 2I
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Midterm Practice #2C

Postby Nha Dang 2I » Mon Feb 12, 2018 2:43 am

How do you know to add the standard enthalpy of sublimation of carbon rather than subtracting it?

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Re: Midterm Practice #2C

Postby Chem_Mod » Mon Feb 12, 2018 9:48 am

Conceptually, we know it takes energy input (endothermic) to go from solid to liquid, and from liquid to gas. We can infer that to go from solid tk gas (sublimation), we will need energy to be used (endothermic) so the enthalpy change will be positive or added.

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