Chapter 10, Problem 10.77QP

Interpretation Introduction

Interpretation: The pressure used in the given freezing and drying process is to be classified as lower or higher than the pressure at the triple point of ${\text{H}}_{\text{2}}\text{O}$. An explanation for the same is to be stated.

Concept introduction: Freeze-drying is a process in which sublimation and desorption process is involved. In this process, frozen solvents or ice are removed from the substance through sublimation and water molecules are removed through desorption.

Freeze-drying is one of the methods for preserving the food.

Sublimation is a process in which the substance in a solid state is directly converted into a vapor state without going through the liquid state.

Desorption is a process in which water molecules are lost during the process.

To explain: If pressure required for the freeze-drying process is lower than the pressure at the triple point of ${\text{H}}_{\text{2}}\text{O}$.