Final answer:
True, freezing-point depression is a measure of osmolality. It reflects the change in freezing point caused by the presence of a solute and is determined using the freezing point depression constant in relation to the molal concentration of the solute.
Step-by-step explanation:
True, freezing-point depression is indeed a measure of osmolality. Freezing-point depression is the process where the freezing point of a solution is lower than that of the pure solvent. This phenomenon occurs because the presence of a solute disrupts the ability of the solvent molecules to form a solid, hence requiring a lower temperature to freeze.
The relationship between the decrease in freezing point (ΔTf) and the concentration of the solute is quantified by the freezing point depression constant (Kf). This constant, specific to each solvent, is used in the equation ΔTf = mKf, where m represents the molality (moles of solute per kilogram of solvent) of the solution. A crucial aspect to remember is that the freezing point depression relies on the number of particles in the solution and not on their identity. As a result, ionic compounds like NaCl can cause a significantly higher freezing point depression compared to non-ionic solutes like glucose, at the same molal concentration.