Phase Equilibria Flashcards
In separation processes, equilibrium is achieved by satisfying the ff conditions
Thermal Equilibrium
Mechanical Equilibrium
Chemical Potential Equilibrium
Phase rule is discovered by
J. Willard Gibbs
this relates the variance (degrees of freedom) F for a
nonchemically reactive system at heterogeneous
equilibrium to the number of coexisting phases P and
the number of components (chemical species) C
present
Phase rule
number of intensive
properties required to completely define the state of
the system
degrees of freedom, F
For a binary vapor-liquid mixture in equilibrium, F = ?
2
Useful in determining
phase states, phase-
transition temperatures,
phase compositions, and
phase amounts for a
given pressure.
T–x–y Diagram
Useful because the vapor
and liquid compositions
are points on the
equilibrium curve and
useful in geometric
constructions.
y–x Diagram
Mixture conditions above the saturated vapor curve
superheated vapor
conditions
below the saturated liquid curve
subcooled liquid
can be constructed to determine the equilibrium vapor and liquid compositions at a
temperature
Tie line
relative amounts of vapor and liquid phases are determined using
inverse lever arm rule
Azeotropic mixtures exhibit mainly _________ where the under isobaric
conditions, the azeotrope boils at a temperature lower than the boiling points of either of the two pure
components.
minimum-boiling azeotropes
shows an azeotrope boiling at a temperature greater
than the boiling points of either of the two pure components
maximum-boiling azeotropes
The curve within the diagram is called ______ which are determined by a ______
miscibility limits
cloud-point titration
Any point inside the miscibility limit is a ______ mixture while outside of it is a ____ mixture.
two-phase
One-phase
