Question

Put dry grapes in a dish with water. What is the change in the raisins after some time? Why? Give seientific reason.

Answer 1

Osmosis is the movement of water molecules from a region of lower concentration of solute ( inside raisin)  to a region of higher concentration of solute (sugar solution )  through a semipermeable membrane. When raisin is put into sugar solution, it shrinks and wilts due to the phenomenon of exosmosis. If the water concentration inside the cell is higher than the sugar medium, the sugar medium is said to be hypertonic solution. Here, the number of water molecules diffusing out will be more than the molecules entering the cell. The cell will shrink due to exosmosis.

Answer 2

The water present around will get inside them making them swell up.This is due to osmosis(endosmosis). When raisinsare soaked in water, they swell. All this is due to the process of osmosis. Thewater molecules pass the cell membrane of the raisins and theraisins thus get swollen.