An isochoric process, also called an isometric process, is a thermodynamic process in which the volume stays constant; $\backslash Delta\; V\; =\; 0$. This implies that the process does no pressure-volume work, since such work is defined by

$\backslash Delta\; W\; =\; P\; \backslash Delta\; V$,

where P is pressure (no minus sign; this is work done by the system).

By applying the first law of thermodynamics, we can deduce that Q, the change in the system's internal energy, is

$Q\; =\; \backslash Delta\; U$

for an isochoric process: all the heat being transferred to the system is added to the system's internal energy, U. If the quantity of gas stays constant, then this increase in energy is proportional to an increase in temperature,

$Q\; =\; n\; C\_V\; \backslash Delta\; T$

where C_V is molar specific heat for constant volume.

On a P-V diagram, an isochoric process appears as a straight vertical line.

See also

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• Adiabatic process
• Cyclic process
• Isobaric process
• Isothermal process
• Polytropic process

Thermodynamics

Izochorický děj | Isokor | Isochore Zustandsänderung | Isochore | Trasformazione isocora | 定積過程 | Isochoor proces | Przemiana izochoryczna | Izohorna sprememba