Delta Hº versus delta H

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105169446
Posts: 32
Joined: Fri Sep 28, 2018 12:16 am

Delta Hº versus delta H

Postby 105169446 » Sun Jan 27, 2019 10:47 pm

In lecture, Prof Lavelle alternates between delta H and delta Hº. Is there a difference between the two? If there is, I which situation should I use which symbol?

Bryant Vong 2G
Posts: 32
Joined: Fri Apr 06, 2018 11:05 am

Re: Delta Hº versus delta H

Postby Bryant Vong 2G » Sun Jan 27, 2019 10:48 pm

Delta H0 stands for the original delta H.

404975170
Posts: 68
Joined: Thu Jul 27, 2017 3:00 am

Re: Delta Hº versus delta H

Postby 404975170 » Sun Jan 27, 2019 10:48 pm

I believe they are the same.

WilliamNguyen_4L
Posts: 65
Joined: Fri Sep 28, 2018 12:28 am

Re: Delta Hº versus delta H

Postby WilliamNguyen_4L » Sun Jan 27, 2019 11:42 pm

Delta H is just the difference between the final and initial values of H. Delta Hº is the value of the difference between the final and initial values of H when the products and reactions are at standard conditions.

Daisylookinland
Posts: 46
Joined: Fri Sep 28, 2018 12:28 am

Re: Delta Hº versus delta H

Postby Daisylookinland » Mon Jan 28, 2019 1:27 pm

deltaH^0 refers to the standard reaction enthalpy (the rxn enthalpy when all R and P are in their standard state). DeltaH is the general symbol for the amount of heat absorbed or released. There is also deltaHf^0 which refers to the Standard Enthalpy of Formation (the standard rxn enthalpy for the formation of 1 mol of a substance).

George Ghaly 2L
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Re: Delta Hº versus delta H

Postby George Ghaly 2L » Tue Jan 29, 2019 7:46 pm

They mean the same thing, one is just referring to the initial delta H.

Kelsey Warren 1I
Posts: 60
Joined: Fri Sep 28, 2018 12:15 am

Re: Delta Hº versus delta H

Postby Kelsey Warren 1I » Tue Jan 29, 2019 7:49 pm

Delta H naught is just delta H in standard/ideal conditions. You use them the same but one is for standard conditions.

Megan_Ervin_1F
Posts: 78
Joined: Fri Sep 28, 2018 12:18 am

Re: Delta Hº versus delta H

Postby Megan_Ervin_1F » Wed Jan 30, 2019 1:35 pm

Does this apply to all other variables as well?


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