Quiz 1 Preparation, Question #4

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Noor_Burney_1L
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Joined: Wed Sep 21, 2016 2:55 pm

Quiz 1 Preparation, Question #4

Postby Noor_Burney_1L » Sun Jan 22, 2017 12:24 am

On Quiz 1 Preparation question #4 (page 113) in the course reader, it asks to calculate the standard enthalpy of vaporization of liquid bromine when given the standard enthalpy of sublimation as well as the standard enthalpy of fusion. In order to solve this, would you use the equation: Standard enthalpy of sublimation= Standard enthalpy of vaporization + Standard enthalpy of fusion?
And then would you manipulate the equation by setting the equation equal to the standard enthalpy of vaporization instead in order to solve for the standard enthalpy of vaporization, and end up getting the answer to be +29.5 Kj/mol?

Melody Li 2L
Posts: 11
Joined: Fri Jul 22, 2016 3:00 am

Re: Quiz 1 Preparation, Question #4

Postby Melody Li 2L » Wed Jan 25, 2017 10:09 pm

Hello,
Yes, your approach to this question is correct. The enthalpy of sublimation is equal to enthalpy of fusion + enthalpy of vaporization. Therefore, just substitute each enthalpy value into the equation and solve for enthalpy of vaporization. The answer should be 29.5 kJ/mol.


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