Phase equilibrium I: Definition of phase

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Phase equilibrium I Definition of phase
Definition Phase Part of a system physical
separated from other parts by a distinct boundary.
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Phase equilibrium I Homogeneous and heterogeneous
Definition Homogeneous one phase
only. Heterogeneous more than one phase.
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Phase equilibrium I Vapour pressure and phase
diagram
Vaporization A(l) ? A(g) Condensation A(g) ?
A(l) Phase equilibrium two phases co-exist and
they are in dynamic equilibrium.
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Phase equilibrium IGeneral phase diagram of one
component
Fusion / Vaporization / Sublimation/ Triple
point/ Critical point
High P with low T Solid
High T with low P gas/vapour
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Phase equilibrium I Phase diagram of water
Character Negative slope for fusion
curve. Increase pressure at constant temp. will
cause melting.
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Phase equilibrium I Phase diagram of CO2
Character Triple point is higher than 1.0
atm. Increase temp. at 1 atm / atmospheric
pressure will cause sublimation. i.e. No melting
for dry ice.