Question 10.11: INTERPRETING A PHASE DIAGRAM Freeze-dried foods are prepared...

INTERPRETING A PHASE DIAGRAM

Freeze-dried foods are prepared by freezing the food and removing water by subliming the ice at low pressure. Look at the phase diagram of water in Figure 10.28, and tell the maximum pressure in mm Hg at which ice and water vapor are in equilibrium.

STRATEGY
Solid and vapor are in equilibrium only below the triple-point pressure, $P_t = 6.0 × 10^{-3}$ atm, which needs to be converted to millimeters of mercury.

fig 10.28

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