Process and State Variables
Describing and analyzing processes requires that you can
understand, calculate, and manipulate both process data as well as
state variables.
How would you calculate process variable values from
measurements ?
 Manipulate process flow data

 Interconvert mass, volume, and moles(and their flows)
 Calculate mass(mole) fractions from mole(mass) fractions for a
mixture
 Calculate pressures using a manometer(and explain the concept
of gauge pressure)
 Interconvert between different temperature scales
 Explain the difference between intensive and extensive
variables
Certain calculations require you to know quite a bit about the
"state" of a material(i.e., its state of aggregation(phase),
temperature, pressure, chemical composition, etc.).How can we
quantify properties about a material 's state?
 Calculate State Variables $\hat U$ and $\hat H$

 Define "state variable"
 Explain why one must choose a reference point when calculating
state variables
 Generate "fictitious paths" from your reference state to your
desired state
 Use heat capacities and phase data to calculate $\hat H$ and
$\hat U$ from fictitious paths
 Use tabular data to determine $\hat U$ and $\hat H$