Delta H

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605110118
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Joined: Wed Sep 18, 2019 12:21 am

Delta H

Postby 605110118 » Fri Feb 14, 2020 1:52 pm

How do you find the change in enthalpy for a reaction if you aren't given the values?

Samuel G Rivera - Discussion 4I
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Joined: Sat Aug 17, 2019 12:16 am
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Re: Delta H

Postby Samuel G Rivera - Discussion 4I » Fri Feb 14, 2020 1:56 pm

I would have to see an example of a problem but if it is a reversible, isothermal process and temperature is constant, then Delta H would be 0 in all cases because there would be no heat transfer in and out of the system.

Manav Govil 1B
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Joined: Sat Sep 07, 2019 12:19 am

Re: Delta H

Postby Manav Govil 1B » Sun Feb 16, 2020 10:30 am

Delta H can usually be written as q. This is derived from the equation . , so .

ASetlur_1G
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Joined: Fri Aug 09, 2019 12:17 am

Re: Delta H

Postby ASetlur_1G » Sun Feb 16, 2020 10:47 pm

Manav Govil 1B wrote:Delta H can usually be written as q. This is derived from the equation . , so .


But this is only for when pressure is constant right?

BCaballero_4F
Posts: 94
Joined: Wed Nov 14, 2018 12:22 am

Re: Delta H

Postby BCaballero_4F » Tue Feb 18, 2020 5:02 pm

You would need to use the delta H equation and work with what you are given in the problem, mainly find what is constant and manipulate the equation to reflect that while looking for delta H.

Mai V 4L
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Joined: Fri Sep 28, 2018 12:23 am

Re: Delta H

Postby Mai V 4L » Sun Mar 08, 2020 11:19 pm

Hi oes anyone have a preferred online resource/chart they like to refer to for studying this topic? Like khan academy or a youtube video or something thanks!!

Adriana_4F
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Joined: Fri Sep 28, 2018 12:29 am

Re: Delta H

Postby Adriana_4F » Sun Mar 08, 2020 11:25 pm

ASetlur_1G wrote:
Manav Govil 1B wrote:Delta H can usually be written as q. This is derived from the equation . , so .


But this is only for when pressure is constant right?


yes it is only when pressure is constant

Adriana_4F
Posts: 74
Joined: Fri Sep 28, 2018 12:29 am

Re: Delta H

Postby Adriana_4F » Sun Mar 08, 2020 11:29 pm

Mai V 4L wrote:Hi oes anyone have a preferred online resource/chart they like to refer to for studying this topic? Like khan academy or a youtube video or something thanks!!


https://www.youtube.com/watch?v=zslB7dr-eZA

This video is very helpful!

Jacob Motawakel
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Re: Delta H

Postby Jacob Motawakel » Mon Mar 09, 2020 2:25 am

You can find delta H either through products minus reactants, or Hess's law, or the Gibbs free energy equation delta G = delta H - T delta S

Mai V 4L
Posts: 111
Joined: Fri Sep 28, 2018 12:23 am

Re: Delta H

Postby Mai V 4L » Mon Mar 09, 2020 2:28 pm

Adriana_4F wrote:
Mai V 4L wrote:Hi oes anyone have a preferred online resource/chart they like to refer to for studying this topic? Like khan academy or a youtube video or something thanks!!


https://www.youtube.com/watch?v=zslB7dr-eZA

This video is very helpful!


Thanks a bunch!

WGaines_2E
Posts: 47
Joined: Mon Nov 18, 2019 12:18 am

Re: Delta H

Postby WGaines_2E » Tue Mar 10, 2020 8:40 pm

dH = dU - PdV


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