While performing the experiment with raisins to determine the percentage of water absorbed by them, a student made following measurements : Mass of water in the beaker = 40g; Mass of raisins before soaking = 5g; Mass of raisins after soaking for 2 hours = 8g; Mass of water left in the beaker after the experiment = 35g. The percentage of water absorbed by raisins is :

The percentage of water absorbed by raisins is calculated based on the initial mass of the dry raisins.

Let the initial mass of dry raisins be $W_1 = 5\text{ g}$.

Let the final mass of swollen raisins after soaking be $W_2 = 8\text{ g}$.

The mass of water absorbed by the raisins is given by:

$$\text{Mass of water absorbed} = W_2 - W_1 = 8\text{ g} - 5\text{ g} = 3\text{ g}$$

The percentage of water absorbed is calculated as:

$$\text{Percentage of water absorbed} = \frac{\text{Mass of water absorbed}}{\text{Initial mass of dry raisins}} \times 100 = \frac{8\text{ g} - 5\text{ g}}{5\text{ g}} \times 100$$

This matches Option D.

• Option A is incorrect because it uses the mass of water left in the beaker as the denominator.
• Option B is incorrect because it uses the initial mass of water in the beaker as the denominator.
• Option C is incorrect because it uses the final mass of the swollen raisins ($8\text{ g}$) as the denominator instead of the initial dry mass ($5\text{ g}$).