Question

activiy 2. can anyone answer me please​

Answer 1

Experiment

To determine the percentage of water absorbed by raisins.

Apparatus and materials required:

A bowl, forceps, a common balance, a weight box, blotting paper, and a few raisins.

Theory

This process is called endosmosis. If these swollen raisins are  kept in a concentrated salt or sugar solution (a hypertonic solution), water from the turgid raisins will come out of the cells and they will shrink. This process is called exosmosis.

Procedure:

1. Take three raisins and weigh them on the common balance. Let this value be W1.

2. Keep these raisins in a bowl containing water for 2 hours.

3. Take the raisins out of water and gently dry them with the help of blotting paper.

4. Weigh the soaked swollen raisins again on the common balance. Let this value be W2

Observations:

1. Weight of dry raisins = W1.

2. Weight of swollen raisins =W2.

3. Weight of the water absorbed by raisins = W2 – W1.

4. Percentage (%) of water absorbed by raisins = W2 – W1/W1× 100.

Result:

The soaked swollen raisins weigh more than the dry raisins. This is because the raisins absorbed water by the process of endosmosis.