Isenthalpe change of state

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In thermodynamics , a change of state is referred to as isenthalpic where the enthalpy does not change:


An example of an isenthalpic process is the expansion of a gas through a throttle valve , see Joule-Thomson effect .

According to the equation of state of an ideal gas, the following applies

For ideal gases, the isenthalphic processes are precisely the isotherms .

An isothermal reversible process is always isenthalpic, but the reverse is not true.

The lines of equal enthalpy in the state diagram are also called isenthalps (or throttle curves).