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enthalpy

Line breaks: en|thalpy
Pronunciation: /ˈɛnθ(ə)lpi
 
, ɛnˈθalpi
 
/

Definition of enthalpy in English:

noun

Physics
1A thermodynamic quantity equivalent to the total heat content of a system. It is equal to the internal energy of the system plus the product of pressure and volume. (Symbol: H)
Example sentences
  • Thermogram transition temperatures, enthalpies, and widths at half-height were determined using the software provided with the calorimeter.
  • The internal energy of a system, like the enthalpy, is a state property, so it is fixed when the state of the system is specified.
  • Scanning calorimetry is used as a direct method to reveal the thermodynamic properties of phase transition like transition temperatures and enthalpies.
1.1The change in enthalpy associated with a particular chemical process: most compounds have negative enthalpies of formation
More example sentences
  • In addition, melting requires significant amounts of extra heat, (in thermodynamic terms, the enthalpy of fusion), to break molecular bonds and cause a phase transition from solid to liquid.
  • The enthalpy, entropy, and free energy changes in the opening reaction of each basepair are determined from the temperature dependence of the exchange rates.
  • First, the volume change and the enthalpy change of the protein can be determined in time domain without temperature variation or solvent variation method.

Origin

1920s: from Greek enthalpein 'warm in', from en- 'within' + thalpein 'to heat'.

Definition of enthalpy in:

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