Question

A student soaked 15 g of raisins in 40 mL of water in beaker x and 30 g of raisins in 80 mL of water in beaker Y at room temperature. He measured the quantity of water left in the beakers after about an hour. He would observe that
A)There is no change in the quantity of water in beakers X and Y.
B)The beaker Y has as much water as in the beaker X.
C)The beaker Y has more water than beaker X.
D)The beaker X has more water than beaker Y.

Answer 1

Hint: Osmosis is the passage of solvent molecules across a selectively permeable membrane into an area of higher solute concentration in the direction of which the concentrations of the solution on both sides appear to be equalized. It is a colligative property, meaning that the osmotic pressure depends on the identity of the molar concentration of the solution, but not on it.

Complete answer:
Water absorbed by raisins in beaker (A) will be equal to that absorbed by raisins of beaker (B). Thus, the amount of water absorbed by the raisins of both beakers (A) and (B) was equal. This happened as the water absorbed depends on temperature and both the beakers have water at room temperature.

The principal cause of assistance in many plants is osmotic strain. The turgor pressure applied on the cell wall is intensified by the osmotic penetration of water, until it equals the osmotic pressure, creating a steady state. Water flows out of the cell and the cell shrinks as a plant cell is put in a solution that is hypertonic compared to the cytoplasm. The cell becomes flaccid in doing so. In extreme situations, the cell is plasmolyzed-due to the lack of water pressure on it, the cell membrane disengages from the cell wall. Water flows into the cell as a plant cell is put in a solution that is hypotonic compared to the cytoplasm, and the cell swells to become turgid.

Hence, the correct answer is option (A)

Note: In biological systems, osmosis is a critical operation, since biological membranes are semi-permeable. These membranes are usually impermeable to large and polar molecules such as ions, proteins and polysaccharides, and are permeable to nonpolar or hydrophobic molecules such as lipids, as well as to small molecules such as oxygen, nitrogen, nitric oxide and carbon dioxide.