## Enthalpy and Internal Energy

$\Delta U=q+w$

William Lan 2l
Posts: 73
Joined: Fri Sep 29, 2017 7:07 am

### Enthalpy and Internal Energy

What's the relationship between Enthalpy and Internal Energy? In other words, how do you relate the two? I just need a conceptual explanation.

Vincent Tse 1K
Posts: 30
Joined: Fri Sep 29, 2017 7:05 am
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### Re: Enthalpy and Internal Energy

Not entirely sure, but my take:
Internal energy (U) is basically all the energy in the system.
Enthalpy (H) is the thermodynamic potential, which is internal energy and the work done on/from its surroundings. That latter part can be represented by PV.
There's the first law of thermodynamics (#7 on the first discussion worksheet), which states that H = U + PV. So essentially, internal energy is a component of enthalpy.

Matthew 1C
Posts: 47
Joined: Fri Sep 29, 2017 7:06 am

### Re: Enthalpy and Internal Energy

Internal energy is the energy stored in the system as kinetic and potential energy. Enthalpy is calculated with the internal energy, which is the energy required to make the system, along with the energy required to make room for the system, the product of the pressure and volume.