4D.9) 7th edition  [ENDORSED]

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Katie Frei 1L
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4D.9) 7th edition

Postby Katie Frei 1L » Wed Mar 13, 2019 10:09 pm

Does anyone know why for problem 4D.9 of the 7th edition of the textbook, the enthalpy density is reported as a positive value, when the standard enthalpy of the reaction that was calculated was a negative value? Thank you!!

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Re: 4D.9) 7th edition  [ENDORSED]

Postby Chem_Mod » Fri Mar 15, 2019 10:57 pm

Super long day.

Nothing has a negative density.

The equivalent would be a negative density for water.

-1g/ml it makes no sense.

Similary, there is no negative energy per gram.

Thank you for all the good wishes, hugs, cards, photos, and smiles.

Wishing you all the Best with your finals.

Ziyan Wang 3J
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Re: 4D.9) 7th edition

Postby Ziyan Wang 3J » Thu Oct 10, 2019 12:09 pm

For exothermic reaction the enthalpy is positive, and for endothermic reaction it is negative.

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Re: 4D.9) 7th edition

Postby bloodorangefield » Fri Nov 01, 2019 3:03 am

Exothermic reactions give positive enthalpys while endothermic reactions give negative enthalpy.

Return to “Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)”

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