A student experiments with two solutions containing the same solute concentrations in a beaker that is divided by a semipermeable membrane, as shown.

In which direction will the water move so that the concentrations of the solutions
remain constant on both sides of the membrane?
A in both directions at different rates
B in both directions at the same rates
C toward the right side of the beaker
D toward the left side of the beaker

B in both directions at the same rates

Explanation:

Solutions with the same amount of solute concentration is referred to as ISOTONIC. In an isotonic solution, there is NO net movement of water molecules because there is no osmotic gradient i.e. difference in solute concentrations.

In this case, a student experiments with two solutions containing the SAME SOLUTE CONCENTRATIONS in a beaker that is divided by a semipermeable membrane. Due to the equal amount of solute concentrations in both solutions, water moves into and out each membrane at an equal rate.

In order for the concentrations of the solutions to remain constant on both sides of the membrane, WATER MUST MOVE IN BOTH DIRECTIONS AT THE SAME RATE.