Question

the beaker displayed has a membrane separating it into two halves. the membrane is considered to be freely permeable to water and sodium bicarbonate but not to albumin. the right side of the beaker has a solution of 15% albumin, while the left side is only filled halfway with a 6% albumin solution. after a short period of time, what will have happened to the right side of the beaker.
a. the number of water molecules has decreased, since they passed through the membrane allowing for the water to equalize on both sides
b. the sodium bicarbonate will cause the solution to dissolve and equal out solution percentages
c. the number of albumin molecules has decreased, since they passed through the membrane allowing the solution percentage to equalize
d. the number of water molecules has increased, since they passed through the membrane allowing the solution percentage to equalize

Explanation:

• Osmosis is the movement of water molecules across a semi - permeable membrane from an area of lower solute concentration to an area of higher solute concentration.
• The right side has a higher concentration of albumin (non - permeable solute). So water will move from the left side (lower albumin concentration) to the right side (higher albumin concentration) to try to equalize the concentration gradient.
• Sodium bicarbonate is permeable, so it will not cause a concentration gradient for water movement in the way described in option B. Albumin is not permeable, so option C is incorrect. Water moves towards the higher solute (albumin) concentration, so the number of water molecules on the right side increases, not decreases (option A is wrong).

Answer:

D. the number of water molecules has increased, since they passed through the membrane allowing the solution percentage to equalize