delta U= delta H


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Emily Vainberg 1D
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Joined: Sat Jul 20, 2019 12:15 am

delta U= delta H

Postby Emily Vainberg 1D » Mon Feb 10, 2020 3:06 pm

When does the Internal Energy (delta U) = delta H?

Jessica Castellanos
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Re: delta U= delta H

Postby Jessica Castellanos » Mon Feb 10, 2020 3:23 pm

I think, at constant volume and constant pressure, delta U is equal to delta H.

Dina Marchenko 2J
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Re: delta U= delta H

Postby Dina Marchenko 2J » Sat Feb 15, 2020 6:08 pm

When there is a constant volume or pressure, no expansion or compression work is being done by the system so w=0. When heat is at constant pressure, it equals the enthalpy change, so at constant pressure, delta U is equal to delta H.

Rebekah Alfred 1J
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Re: delta U= delta H

Postby Rebekah Alfred 1J » Sat Feb 15, 2020 7:23 pm

When the volume of the reactants is equal to the volume of the products, delta U is equal to delta H.

Kayla Maldonado 1C
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Re: delta U= delta H

Postby Kayla Maldonado 1C » Sun Feb 16, 2020 3:32 am

Delta U= q+w and under constant pressure, qp=delta H and when no work is done Delta U=Delta H

Leonardo Le Merle 1D
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Re: delta U= delta H

Postby Leonardo Le Merle 1D » Thu Mar 12, 2020 11:52 am

The answers to this question
viewtopic.php?t=25381
Were also pretty helpful for me sorting it out in my head, hope they help!

Jacob Motawakel
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Re: delta U= delta H

Postby Jacob Motawakel » Thu Mar 12, 2020 2:08 pm

under constant volume delta U equals delta H because at constant pressure q equals H and at constant volume no work is being done, so in that case U=q which is U=H in contact pressure and volume.


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