A group of students are conducting an experiment. Since potatoes contain both sugar and water, the students use them in the experiment. The students cut six equal cubes of potato and weigh them. They place the six cubes into six different beakers containing different concentrations of sugar solutions, then weigh each potato cube after 24 hours and calculate the percent change in mass. The graph below shows the result of their experiment.

Which of the statements below is a valid conclusion about this experiment?

a
The lower the concentration of sugar, the more likely the potato will gain mass.
b
The higher the concentration of sugar, the more likely the potato will gain mass.
c
The lower the concentration of sugar, the less likely the potato will gain mass.
d
The higher the concentration of sugar, the more likely the water concentration will be at equilibrium.

1 answer

Based on the experiment described, the concentration of sugar in the solutions affects the mass change of the potato cubes. The principle involved here is osmosis, where water moves from an area of higher concentration (inside the potato) to an area of lower concentration (the sugar solution) if the solution is hypertonic relative to the potato.

From your description, we can analyze the options:

a) The lower the concentration of sugar, the more likely the potato will gain mass.

  • This is true. In lower sugar concentrations (or higher water concentrations), the water will move into the potato cubes, leading to a gain in mass.

b) The higher the concentration of sugar, the more likely the potato will gain mass.

  • This is false. Higher sugar concentrations can cause the potato cubes to lose mass, as water moves out of the potatoes due to osmosis.

c) The lower the concentration of sugar, the less likely the potato will gain mass.

  • This is false based on the logic of osmosis. Lower sugar concentrations will actually lead to more mass gain.

d) The higher the concentration of sugar, the more likely the water concentration will be at equilibrium.

  • This statement is somewhat convoluted and likely misleading; equilibrium in terms of water concentration isn't necessarily linked to the concentration of sugar in a straightforward way.

Given the explanations, the valid conclusion is:

a) The lower the concentration of sugar, the more likely the potato will gain mass.