According to the rules of osmosis, at what point will a system reach a state of equilibrium?
A system will reach equilibrium when the ______ (Answer) on both sides of a water-permeable membrane are equal.
Answers:
a) concentration of solute molecules
b) number of solute molecules
c) number of solvent molecules
d) volume of water
The correct answer and explanation is :
The correct answer is:
d) volume of water
Explanation:
Osmosis is the movement of water molecules across a selectively permeable membrane, from an area of lower solute concentration to an area of higher solute concentration. This movement continues until equilibrium is reached. At equilibrium, the concentration of solute molecules may not necessarily be the same on both sides of the membrane, but the volume of water on both sides will be balanced.
In osmosis, water moves to balance the concentration of solute molecules in different solutions. When there is a difference in solute concentration across the membrane, water will move from the area where the solute concentration is lower (more water, less solute) to the area where the solute concentration is higher (less water, more solute). This is known as the osmotic gradient. The movement of water will continue until the osmotic pressure (the pressure exerted by the solute concentration gradient) is balanced, meaning the system has reached an equilibrium.
However, equilibrium is achieved when the volume of water on both sides of the membrane is equal, as the net movement of water molecules stops. This doesn’t necessarily mean that the concentration of solute molecules on both sides is identical, because osmosis is driven by the need to equalize the volume of water, not the solute concentration. The solute concentration will typically remain different, but the movement of water will cease once the volume of water on both sides is balanced.
Thus, osmosis reaches equilibrium when the volume of water on both sides of the membrane becomes equal, even if the concentration of solute molecules differs.