Practical: Experiment to Investigate Osmosis

What is the purpose of putting potato cylinders into different concentrations of sucrose solution?

To observe the effect of different water concentrations on potato cylinders.

What is the concentration range of sucrose solutions used in the experiment?

From pure water (0.0M) to a very concentrated sucrose solution.

What tool is used to cut the potato into cylinders?

A cork borer.

What should the diameter of the potato pieces be?

About 1 cm.

How long should the potato cylinders be left in the sucrose solution?

At least 40 minutes.

What should be done to the potato cylinders before weighing them after the experiment?

Pat them dry gently with a paper towel.

What does 'M' represent in the context of the sucrose solution?

A unit of concentration, also written as mol dm-3.

What is the independent variable in this potato experiment?

The concentration of the sucrose solution.

What are the control variables in this experiment?

Volume of solution, size of potato cylinders, type of potatoes used, and amount of drying.

How is the percentage change in mass calculated?

(final mass - initial mass) / initial mass x 100.

What does a positive percentage change in mass indicate?

The water concentration in the sucrose solution is higher than in the cylinders, so the cylinders gain mass.

What does it mean when there is no change in mass?

The fluid inside the cylinders and the sucrose solution are isotonic, having the same water concentration.

What happens to the potato cylinders when the sucrose solution has a lower water concentration than inside the cylinders?

The cylinders lose water, causing their mass to decrease.

Why is it important to control variables in this experiment?

To ensure the validity of the results.