Question

Two beakers A and B contain plain water and concentrated sugar solution respectively. Equal number of dried raisins are kept in them for a few hours and then taken out.
(i) Explain the reason for the difference in the physical appearance of raisins which were taken out of the two beakers.
(ii) On the basis of above observation, categorise the two solution as hypotonic and hypertonic

CBSE Class IX Science SA 2 (3 Marks)

Answer 1

Explanation:

• Raisins in beaker A with plain water will get swollen due to endosmosis while raisins in beaker B with saturated sugar solution will get shrink due to exosmosis...

• Plain water is hypitonic saturated sugar solution is hypitonic.....

Answer 2

Answer:

(i) When raisins are submerged in water, the surrounding water diffuses into the raisins, causing them to enlarge due to endosmosis.

Exosmosis causes raisins to shrink when they are immersed in a sugar solution.

(ii)Plain water is the hypertonic solution, on the other hand, the concentrated sugar solution is hypotonic.

Explanation:

(I) Osmosis is the process of moving water from a high-concentration area to a lower-concentration area.

• The transport of solvent into the cell is called endosmosis, while the movement of solvent out of the cell is called exosmosis.

• A sugar solution with a high concentration of sugar and a minimal amount of water is called a high concentration sugar solution.
• When raisins are placed in a sugar solution, they lose water through exosmosis and shrink as a result.

• When raisins are placed in plain water, the water enters the cells of the raisins, causing them to enlarge.
• Endosmosis is the phenomenon behind this activity.
• On the outside, the concentration of water is higher than on the interior.

(ii) In a hypotonic solution, the soluble concentration outside the cell is higher than inside the cell.

• As a result, water molecules travel from within to outside the cell. Concentrated sugar solution belongs to this category

The solution outside the cell in a hypertonic solution is less concentrated than the fluid inside the cell.

• As a result, water molecules enter the cell from the outside. The plain water belongs to this solution