Relation between enthalpy and internal energy

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Sarahi Garza 3k
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Relation between enthalpy and internal energy

Postby Sarahi Garza 3k » Sun Jan 15, 2017 4:42 pm

Why are enthalpy and change of internal equal to one another when no gas is generated or consume in a reaction or system? With no expansion work are the volume and pressure both constant?

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Re: Relation between enthalpy and internal energy

Postby Chem_Mod » Sun Jan 15, 2017 6:59 pm

Enthalpy is the heat flow for a given system, which includes internal energy and the energy used to displace the systems surroundings. If no gas is generated, the work ideally is zero. Thus ∆H = ∆U. Consequently, your second statement must be true if the first is true.


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