Question

A student measures the osmolality of two aqueous solutions, A and B. The student finds that the osmolality of solution B is much higher than solution A. Based on this result, how do solutions A and B likely differ in the concentration of solutes in their solution, and why?

A) Solution A likely is the more concentrated solution because osmolality measures the moles of solute per kilogram of solute.
B) Solution B likely is the more concentrated solution because osmolality measures the moles of solute per kilogram of solvent.
C) Solution A likely is the more concentrated solution because osmolality measures the moles of solute per kilogram of solvent.
D) Solution B likely is the more concentrated solution because osmolality measures the moles of solute per kilogram of solute.

Answer 1

Solution B likely has a higher concentration of solutes compared to solution A, as indicated by its higher osmolality. Osmolality measures the moles of solute per kilogram of solvent, making B the more hypertonic solution.

Step-by-step explanation:

When comparing the osmolality of two aqueous solutions, A and B, and finding that solution B has a much higher osmolality than solution A, it can be concluded that solution B likely has a higher concentration of solutes.

Osmolality is a measure of the number of moles of solute per kilogram of solvent in a solution. Therefore, a higher osmolality indicates a greater number of solute particles in the solution, leading to the assumption that solution B is more concentrated with solutes compared to solution A. For instance, in comparing two sugar solutions, the one with more sugar dissolved in the same amount of water would be considered hypertonic, meaning it has a higher solute concentration, compared to a solution with less sugar, which would be considered hypotonic.