Delta U vs Delta H

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Kate Swertfager
Posts: 50
Joined: Wed Sep 18, 2019 12:17 am

Delta U vs Delta H

Postby Kate Swertfager » Sun Feb 02, 2020 6:07 pm

What’s the difference between the delta U and delta H? How do I know when to use which one?

Angela Wu-2H
Posts: 50
Joined: Fri Aug 30, 2019 12:16 am

Re: Delta U vs Delta H

Postby Angela Wu-2H » Sun Feb 02, 2020 6:17 pm

Delta U is the change in internal energy; meanwhile, delta H is enthalpy, or the change in heat.

Posts: 111
Joined: Fri Aug 09, 2019 12:16 am

Re: Delta U vs Delta H

Postby claudia_1h » Sun Feb 02, 2020 6:19 pm

Delta U is given by the energy supplied to the system by heat (q) plus the energy transferred by compression work (w). When the system is under constant pressure, q is equal to Delta H, so Delta H becomes a part of how Delta U is calculated.

Aarushi Solanki 4F
Posts: 107
Joined: Sat Jul 20, 2019 12:17 am

Re: Delta U vs Delta H

Postby Aarushi Solanki 4F » Sun Feb 02, 2020 6:23 pm

Delta U indicates internal energy, and is composed of both delta H (enthalpy) and work. When no work is done, Delta U is equal to delta H. When no energy is transferred through heat and delta H is therefore 0, then Delta U is equal to work.

Radha Patel 4I
Posts: 97
Joined: Tue Feb 12, 2019 12:15 am

Re: Delta U vs Delta H

Postby Radha Patel 4I » Sun Feb 02, 2020 6:32 pm

DeltaU is change in internal energy
DeltaH is change in enthalpy
The basic formulas that they derive from :
DeltaU= q + w
DeltaH=DeltaU + P*DeltaV

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