A student investigated the effect of different concentrations of sugar solution on pieces of potato - AQA - GCSE Biology Combined Science - Question 1 - 2020 - Paper 1

The potato increased in mass because it gained water through the process of osmosis. In this case, the concentration of water outside the potato was greater than inside the potato cells, leading to water moving into the cells.

Plot the data from Table 1:

• The points should be plotted as (concentration, change in mass).
• A line of best fit should be drawn across the plotted points, indicating the trend in the data.

Make sure the x-axis represents the concentration of sugar solution (mol/dm²) and the y-axis represents the change in mass (g).

From Figure 1, when the mass of the potato remains constant, the concentration of sugar solution inside the potato cells is approximately between 0.23 and 0.24 mol/dm².

Using the given formula, we calculate:

Change in mass = 0.25 g Mass of potato at start = 7.96 g

Percentage change in mass = ( \frac{0.25}{7.96} \times 100 \approx 3.14 )%

Thus, the percentage change in mass, rounded to three significant figures, is 3.14%.