## delta U= delta H

$\Delta U=q+w$

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

### delta U= delta H

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

Jessica Castellanos
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### Re: delta U= delta H

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

Dina Marchenko 2J
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Joined: Thu Jul 25, 2019 12:16 am

### Re: delta U= delta H

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

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

Posts: 107
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### Re: delta U= delta H

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

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

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.