Standard Reaction Enthalpy vs Standard Enthalpy of Formation

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Kathryn 1F
Posts: 66
Joined: Fri Sep 28, 2018 12:19 am

Standard Reaction Enthalpy vs Standard Enthalpy of Formation

Postby Kathryn 1F » Sun Jan 27, 2019 8:13 pm

I am confused on the difference between Standard Reaction Enthalpy and Standard Enthalpy of Formation and how they are connected to each other. They seem to be defining the same thing which is enthalpy when all the elements are in the standard state?

Steven Garcia 1H
Posts: 79
Joined: Fri Sep 28, 2018 12:16 am

Re: Standard Reaction Enthalpy vs Standard Enthalpy of Formation

Postby Steven Garcia 1H » Sun Jan 27, 2019 8:49 pm

If I interpreted correctly, I believe that the standard enthalpy of formation is just a special case of the standard reaction enthalpy. The standard reaction enthalpy refers to the amount of heat released or taken up by a rxn when all the elements (reactants and products) are in their standard state (1atm). The standard enthalpy of formation refers to the enthalpy change between the reactants and products when all the elements are in their standardized form.

I would say they more or less they mean the same thing. However reaction enthalpy is different because for reaction enthalpy the reactants/ products are not in their standardized state.


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