L1 /   
7
CH1012
SOME USES
When is it valid to use these diagrams?
- in a closed system
1 atm.
H2O
- when the system is at equilibrium
Sublimation  if pext < ptp 
then sublimation occurs
Freeze Drying
1) freeze sample:      water        ® ice crystals
2) pump on sample: solid (ice) ® gas (»1mtorr)