Question

A student put together the experimental setup shown above. The selectively permeable membrane is permeable to both types of solute molecules shown.27. Do you expect the distribution of solutes on each side of membrane to changeover time? Explain.28. Redraw the apparatus making an inference as to where molecules C and D willbe when it reaches equilibrium.29. Once equilibrium is reached will the molecules continue to move? Explain.

Answer 1

First of all, the problem says that the membrane is selectively permeable.

Permeable means that it allows molecules to pass from one side to another (and vice-versa).

On the other hand, we have the concept of selectively, which means that not all types of molecules are allowed to cross through the membrane, but in this case, it also says that the membrane it's permeable for both molecules.

So, in this case:

27) Yes, in order to reach the equilibrium, the molecules will move, until there is an equal amount of each of them on both sides of the membrane.

28) The important thing here is not how many molecules of each type you draw on each side, but the amount of them should be the same on both sides. Take into count that we are not having in count the interaction between the molecules either.

29) Yes the will, because of the permeable property of the membrane. This is the reason why this equilibrium it's called a dynamic equilibrium.