Two newly prepared solutions, A and B, contain a red dye. Solution A is darker in color than solution B. We will make two experimental observations: Experiment 1: A and B are placed, side-by-side, separated by a semipermeable membrane through which only water can pass. Experiment 2: A and B are placed, side-by-side, separated by a plastic sheet with pin holes. What will happen if we carefully measure the color intensity of solution B after an hour or two

The intensity of solution B will increase in experiment 1

But it will remains constant in experiment 2

Explanation:

Experiment 1 - When solution A and solution B are separated by a semipermeable membrane, only water can flow from region of higher concentration to the region of lower concentration. Since, solution B is lighter in color than the solution A, the number of colorings solute particle is higher in solution A. This also suggests that the water concentration is higher in solution B. Thus, water will move from solution B to solution A thereby making it darker in color

Experiment 2 -

Pin holes are created but the movement of solute and solvent is only possible if there is difference in quantity of both the solutions. Holes in plastic sheet has nothing to do with the concentration of solute or solvent.