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enthalpy

Posted: Thu Jan 18, 2018 11:03 am
by Dang Lam
Is delta Hf the same as delta Hrxn?

Re: enthalpy

Posted: Thu Jan 18, 2018 11:09 am
by Fatima_Iqbal_2E
Not necessarily. Delta Hf is the enthalpy of formation, while Delta Hrxn is the enthalpy of reaction. Generally, problems will ask you to find the enthalpy of reaction using the enthalpies of formation of the reactants and products. Additionally, the enthalpies of formation are for one molecule, while the enthalpies of reaction are for the reaction as a whole.

Re: enthalpy

Posted: Thu Jan 18, 2018 11:23 am
by Ryan Sydney Beyer 2B
In addition to these two types of enthalpies you might want to be familiar with enthalpies of fusion, enthalpies of vaporization and when to use them. I'm sure you won't have to memorize any values but just be aware of when to use them as we might get a problem of melting ice or something along those lines.

Re: enthalpy

Posted: Thu Jan 18, 2018 11:26 am
by Sally Nason - 1K
When you subtract the enthalpies of formation of the reactants from the enthalpies of formation of the products, the result is the enthalpy of the reaction.