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An intensive property is a physical quantity whose value does not depend on the amount of substance which was measured. The most obvious intensive quantities are ratios of extensive quantities. In a homogeneous system divided into two halves, all its extensive properties, in particular its volume and its mass, are divided into two halves.
If the units were changed from per mass to, for example, per mole, the property would remain as it was (i.e., intensive or extensive). ... (constant pressure) C p: J/K
The final column lists some special properties that some of the quantities have, such as their scaling behavior (i.e. whether the quantity is intensive or extensive), their transformation properties (i.e. whether the quantity is a scalar, vector, matrix or tensor), and whether the quantity is conserved.
Enthalpy is an extensive property; it is proportional to the size of the system (for homogeneous systems). As intensive properties, the specific enthalpy, h = H / m , is referenced to a unit of mass m of the system, and the molar enthalpy, H m = H / n , where n is the number of moles.
An intensive property does not depend on the size or extent of the system, nor on the amount of matter in the object, while an extensive property shows an additive relationship. These classifications are in general only valid in cases when smaller subdivisions of the sample do not interact in some physical or chemical process when combined.
The pressure is the intensive generalized force, while the volume change is the extensive generalized displacement: δ W = P d V . {\displaystyle \delta W=P\,\mathrm {d} V.} This defines the direction of work, W {\displaystyle W} , to be energy transfer from the working system to the surroundings, indicated by a positive term.
Here, U is internal energy, T is absolute temperature, S is entropy, P is pressure, and V is volume. This is only one expression of the fundamental thermodynamic relation. It may be expressed in other ways, using different variables (e.g. using thermodynamic potentials ).
The intensive (force) variable is the derivative of the internal energy with respect to the extensive (displacement) variable, while all other extensive variables are held constant. The thermodynamic square can be used as a tool to recall and derive some of the thermodynamic potentials based on conjugate variables.