Internal Energy: Definition & Difference from Enthalpy of Formation

Thread starter Bashyboy
Start date Jan 6, 2012
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Definition Difference Energy Enthalpy Formation Internal Internal energy

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Internal energy is defined as the total energy contained within a system, encompassing the kinetic and potential energy of its particles. It is distinct from enthalpy, which is the total heat content of a system at constant pressure and includes internal energy plus the product of pressure and volume. The confusion arises because both concepts relate to energy within a system, but they serve different purposes in thermodynamics. Enthalpy of formation specifically refers to the change in enthalpy when one mole of a compound is formed from its elements in their standard states. Understanding these definitions clarifies their roles in thermodynamic processes and calculations.

Jan 6, 2012

Bashyboy

I am reading on wikipedia about internal energy and the describe it as the energy required to create a system. Ithought that this was the definiton for enthalpy of formation. Was it meant by the definition of internal energy?

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Jan 7, 2012

Borek

Mentor

Bashyboy said:

Ithought that this was the definiton for enthalpy of formation.

Check the enthalpy definition then.

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