© Dr. Steve Rapp, 2005

Rules Pertaining to State and Path
Quantities

nThe water volume in the system (extensive state quantity) is changed by adding or draining water volume (extensive path quantities).

8. Algebraic combinations of state quantities are also
state quantities. Example; Specific enthalpy *H*, which is
defined as the sum of specific internal energy U and PV. *H* = U + PV

Because U, P, and V are all
state quantities, then *H* must also
be a state quantity.

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